/ 

Steam Heating foe Buildings; 



OK 



HINTS TO STEAM FITTERS. 



BEING A 

DESCRIPTION OF STEAM HEATING APPARATUS FOR WARMING AND 

VENTILATING PRIVATE HOUSES AND LARGE BUILDINGS, WITH 

REMARKS ON STEAM, WATER, AND AIR, IN THEIR 

RELATION TO HEATING ; TO WHICH ARE ADDED 

USEFUL MISCELLANEOUS TABLES. 



BY 






WILLIAM J. BALDWIN, 

Member American Society of Mechanical Engineers. 



WITH MANY ILLUSTRATIONS. 



FOURTH EDITION. 

NEW YORK : 

JOHN WILEY & SONS, 

15 Astor Place. 

1883. 



' n 7510I 



Copyright, 

1881, 

By JOHN WILEY & SONS. 



By Transfer 

Treasury Dep 

S ^P 2 3 1936 



^ 



PRESS OF J. J. LITTLE & CO., 
NOS..I0 TO JO ASTOR PLACE, NEW YORK. 






PEEFACE 



The dearth of practical information on steam heat- 
ing, and the want felt by the young , steam-fitter, in 
almost all branches of his trade, has suggested to me 
the necessity of explaining, so far as lies in my power, 
some of the many questions which often arise. 

This volume has no scientific pretensions beyond what 
are actually necessary to explain a few laws, which 
affect the action of steam, water, and air, within pipes ; 
and is simply a Vade Mecum of practical results to the 
fitter which the trade has tacitly adopted — from re- 
peated failures at first it has come to practical success 
eventually. These results I call "Hints," since I make 
many assertions I do not explain, which are known to be 
facts, and which will be of more real value to a beginner, 
than a long-drawn exhortation of both sides of the 
question, defeating its own object by leaving the stu- 
dent undecided. 

Most of the tables, and all of the diagrams but one, 
were especially made for this volume. 




CONTENTS 



CHAPTER I. 



GRAVITY CIRCULATING APPARATUS. 

PAGE 

1 Gravity Systems of Piping 1 

2 Nomenclature 3 

3 Water-]ine 5 

4 How a Building is Piped 6 

5 Two Heaters from the same Connection G 

6 Outlets of the Risers 7 

7 Risers 7 

8 Radiator Connections 8 

9 Steam-mains (see Chapter XV.) 9 

10 Return of the Water under all Conditions of Pressure 10 

11 The Size of Mains 10 

12 How Steam-pipes should leave the Boiler 11 

13 Relief Pipes 11 

14 Pitch of the Main 12 

15 Tees in a Main 12 

16 Stop-valves in Risers 12 

17 Stop-valves in Mains 13 

18 Main Return-pipes 14 

19 Dry Return-pipes 15 

20 Check- valves in Returns 15 

v 



vi CONTENTS. 

CHAPTER II. 

RADIATORS AND HEATING SURFACES. 

PAGE 

21 Vertical Tube Radiators 17 

22 Steam Entering a Radiator 18 

23 Cast-iron Radiators 20 

24 Sheet-iron Radiators 21 

25 Coils 21 

26 To Estimate Heating Surfaces for Direct Radiation 22 

27 Isolated Buildings 24 

CHAPTER III. 

CLASSES OF RADIATION. 

28 How Direct Radiating Surfaces should be Placed 26 

29 Indirect Radiators 27 

30 Indirect Radiator Boxes 28 

31 Air-flues 28 

32 Change of Air in Rooms 30 

33 Direct-indirect Radiation 30 

34 Position for Indirect Heaters with the Action of Air in Rooms, 

etc. , and the Cause of Cold Feet 32 

35 Cold-Air Inlet-ducts 34 



CHAPTER IV. 

HEATING SURFACES OF BOILERS. 

36 Fire-box and Flues 36 

37 Crowding the Fire-box with Hanging Surfaces 38 

38 Corrugated Fire Surfaces 39 

39 Boilers which have Given the Best Results 39 

40 Proportioning Boilers 40 

41 Can a Boiler be Robbed of its Heat by the Gases of Combus- 

tion ? 40 

42 Reverberatory or Drop Flue Boilers 41 

43 Will the Quantity of Water within a Boiler Effect Evapora- 

tion ? 41 



CONTENTS. vii 
CHAPTER V. 

BOILERS FOR HEATING, ETC. 

PAGE 

44 Simplicity of Parts 42 

45 Requirements for House Boilers 43 

46 Construction of Upright Boilers 45 

47 Construction of Horizontal Boilers 46 

48 Contracted Passages under Boilers 46 

49 Technical Names of Parts of Boilers, and their Setting 47 



CHAPTER VI. 

FORMS OF BOILERS USED IN HEATING. 

50 A Source of Danger to the Fitter 49 

51 Upright Boiler without Tubes 49 

52 Upright Multi-tubular Boiler 50 

53 Upright with Steam-dome 51 

54 Upright Drop-tube Boiler 52 

55 Base-burning Boiler 56 

5G Horizontal Tubular Boilers 57 

56£ Horizontal Multi-tubular Boilers 60 



CHAPTER VII. 

REMARKS ON BOILER SETTING. 

57 Thickness of Walls 63 

58 Marshy or Sandy Ground 63 

59 Why Boiler Walls Crack 63 

60 Fire-bricks in a Furnace 65 

61 Front-connection Division 65 

62 Dead Plates 67 

63 Bridge-walls 67 

64 Ash-pits 67 

65 Lugs on Boilers 67 



v iii CONTENTS. 

CHAPTER VIII. 

PROPORTION OF THE HEATING SURFACES OF BOILERS TO THE HEATING 

SURFACES OF BUILDINGS. 

PAGE 

66 Relation of Boiler to Heaters 69 

CHAPTER IX. 

RELATION OF GRATES AND CHIMNEYS TO BOILERS. 

67 Grate of a House Boiler 74 

68 Size of Grate to Boiler 75 

69 Size of Chimneys 75 

70 Examples of Grates and Chimneys 76 

71 Ta' le of Grates and Chimneys 78 

72 Conclusions Drawn 78 

73 Why Grates Break ? 80 

CHAPTER X. 

SiFETY VALVES. 

74 Boilers Bursting when Working at Ordinary Pressures 83 

75 The Office of the Safety-valve 83 

76 Decrease of Pressure under the Valve 84 

77 Table of Lift of a 4-inch Valve at various Pressures 84 

78 Graphic Illustration of the Size of the Opening of a 4-inch Valve 

when Blowing off at various Pressures 85 

79 Formulas for Calculating the Size of Safety-valves 86 

80 Construction and Operation of Safety-valves 87 

CHAPTER XI. 

DRAFT REGULATORS. 

81 Diaphragms 91 

82 Construction of Regulators 92 

83 Connecting Regulators 94 



CONTENTS. i x 



84 Doors to be Regulated 94 

85 Construction of Doors for Regulator 95 



CHAPTER XII. 

AUTOMATIC WATER-FEEDERS. 

86 Construction 96 

87 When a Water-feeder should be used 98 

88 Connections to Water-feeders 98 

89 Draught in Pipes 99 

CHAPTER XIII. 

AIR-VALVES ON RADIATORS. 

90 Where they should be Placed 100 

91 Drawing Air from Coils, etc 100 

92 Air-valves, Construction and Design 102 

93 Waste of Water from Air-valves at High Pressure 105 



CHAPTER XIV. 

WKOUGHT-IRON PIPE. 

94 Description of Pipe , , 106 

95 Nominal Size of Pipe , , 106 

96 Table of Standard Dimensions of Pipes 10? 

97 How to Calculate the Relative Areas of Pipes 108 

98 Table of Relative Areas of Pipes 110 

99 Diagram of Relative Areas of Pipes 112 

100 Expansion of Pipes and its Relation to Steam-mains 113 

101 Expansion of Return-pipes 114 

102 Effect of Lime and Moisture on Pipes 115 

103 Expansion of Pipes Buried in the Ground 115 

104 Expansion- joints and how to Compensate without them , . 115 

105 Connecting Boiler, Domes, etc . 116 



x CONTENTS. 

PAGE 

106 Expansion of Cast-iron 118 

107 Expansion of Wrought-iron 118 

108 A Table of Linear Expansion of Wrought and Cast Iron Pipes 119 



CHAPTER XV. 

MAIN-PIPES. 

109 Size of Mains 120 

110 Loss of Heat from Imperfect Apparatus 120 

111 Heat or Power Necessary to put Water into Boilers 122 

112 Poor Economy to Use Small Piping 122 

113 Necessity for Providing for a Direct Return 123 

114 How to Determine the Size of the Main 123 

115 The Unit of Size in Pipes 124 

116 Relation between Heating Surface and Diameter of Pipe 124 

117 Diagram of the Size of Main-pipes for Gravity Apparatus 125 



CHAPTER XVI. 

STEAM. 

118 Temperature of Steam 128 

119 Technical Terms 128 

120 Table of Elastic Force, Temperature, and Volume of Steam. . 130 

121 Calculations on Steam, Water, etc 131 

122 Diagram of Rankine's Formula 132 



CHAPTER XVII. 

HEAT OF STEAM. 

123 The Unit of Heat 134 

124 Sensible and Latent Heat of Steam 134 

125 A Diagram of Sensible and Latent Heat of Steam and Water. 137 

126 Equivalents of Heat 138 



CONTENTS. xi 

CHAPTER XVIII. 



AIR. 

PAGE 

127 What Air Is.... 140 

128 Air Necessary for an Adult 141 

129 Specific Weight and Volume 141 

130 Expansion of Air 142 

131 Watery Vapor in the Atmosphere 144 

132 Quantity of Moisture Air is Capable of Taking Up 144 

133 Drying Power of Air 145 

134 A Table of the Watery Vapor Air is Capable of Taking Up. . . 145 

135 Saving in Time by High Temperatures in the Drying Room. . 146 

136 What Does Ventilation Cost ? 146 



CHAPTER XIX. 

HIGH-PRESSURE STEAM USED EXPANSIVELY FOR HEATING. 

137 Systems 150 

138 The Holly System 151 

CHAPTER XX. 

EXHAUST STEAM AND ITS VALUE. 

139 Thermal Value 159 

140 How Hot can Feed-water be Made 160 

What Percentage of the Coal Heap does the Heating of the 
Feed-water Represent 160 

How much of the Exhaust Steam can be used in Warming the 
Feed -water 161 

141 Warming Buildings with Exhaust Steam 162 

142 Loss from Back Pressure 162 

143 Exhaust and Live Steam in the same Coils 163 



xii CONTENTS, 

CHAPTER XXI. 

BOILING AND COOKING BY STEAM, AND HINTS AS TO HOW THE APPARATUS 
SHOULD BE PIPED. 

PAGE 

144 Steaming and Vegetable Steamers 165 

145 Steam-kettles 170 

146 Warming Water in Tanks 176 

147 Warming Water at the Nozzle or Cock 177 

148 Warming Water for Baths, etc., when there is no Steam- 

boiler 178 



CHAPTER XXII. 

DRY BY STEAM. 

149 Description 180 

150 Laundry-drying 182 

151 Dry Kilns and Other Modes of Drying 186 



CHAPTER XXIII. 

STEAM-TRAPS. 

" CHAPTER XXIV. 

BOILER CONNECTIONS AND ATTACHMENTS. 

157 Feed-pipes, Blow-off Cocks, Valves, Gauges, etc 200 

CHAPTER XXV. 

MISCELLANEOUS ARTICLES . 

158 Cutting Walls and Covering Risers 206 

159 Turning Exhaust Steam into Chimneys 207 

160 Soldering of Pipes and Brass Fittings 209 

161 Painting Pipes 210 



CONTENTS. xiii 

CHAPTER XXVI. 

PAGE 
MISCELLANEOUS NOTES AND TABLES OF SERVICE IN ESTIMATING 211 

APPENDIX A. 

SPECIFICATION FOR A STEAM-HEATING APPARATUS, INCLUDING COOK- 
ING, WASHING, AND DRYING 223 

APPENDIX B. 

PLURAL BOILER SPECIFICATIONS 235 





INTRODUCTION. 



Within twenty years, the warming of buildings with 
steam carried through pipes became a science ; pre- 
viously, it was a chaotic mass of pipes, and principles. 

A low-pressure gravity apparatus is the most health- 
ful, economical, and perfect heating appliance known, 
and may be constructed to heat a single room, or the 
largest building, with a uniformity which cannot be at- 
tained by any other means. 

By a gravity apparatus is meant, one without an out- 
let, whose circulation is perfect, wasting no water, and 
requiring no mechanical means to return the water to 
the boiler. It may be likened to the circulation of the 
blood — the boiler being the heart ; the steam-pipes, the 
arteries ; and the return-pipes, the veins : thus carrying 
heat and life into every part of a building. 

When reference is made to steam-pressure in this 
volume, it is understood to mean pressure above the 
atmosphere. Nearly all tables of reference on steam are 
given in absolute pressures — namely, pressures includ- 
ing the pressure of the atmosphere— which unapparent 
pressure has to be overcome before it is appreciable on 
a steam-gauge ; and, as the steam-fitter has little, if 
anything, to do with pressures below atmosphere, the 
tables, etc., herein used will be modified, to commence 



xv i INTRODUCTION. 

at atmospheric pressure (l^V pounds of the absolute 
scale), thus conveying comparison in the ordinary terms 
to which the steam-fitter is accustomed ; and preventing 
the necessity of a mental calculation, which always in- 
volves fractions, and enjoins a task which should not 
be thrown on a beginner. Therefore, all pressures men- 
tioned will be apparent pressures — namely, pressures 
that would be indicated by a prroperly regulated steam' 
gauge. 



BALDWIN'S 

STEAM HEATING FOE BUILDINGS. 



CHAPTEK I. 

GRAVITY CIRCULATING APPARATUS. 

1. The loiv-pressure gravity circulation is at present 
very much used in the steam heating of private houses, 
churches, and schools. Its principal merits, when well 
done, are : It is safe ; noiseless ; the temperature of the 
heating surface is low and uniform ; all the water of 
condensation is returned into the boiler, except a very 
small loss from the air-valves ; it is easy to keep the 
stuffing-boxes of the heater-valves tight ; and it is no 
more trouble to manage than a hot-water apparatus. 

There are four systems of low-pressure steam-piping, 
whose principal features are : 

1st. Main distributing pipes and distributing risers, 
with corresponding return mains and risers (see Fig. 1, 
at A). 

2d. Main distributing pipes and distributing risers, 
with a corresponding return main, and a separate return 
riser for every coil or heater; the return risers not con- 

1 




SYSTEMS OF PIPING. 
Fig. 1 



BALDWIN'S 

STEAM HEATING FOR BUILDINGS. 



CHAPTEE I. 

GRAVITY CIRCULATING APPARATUS. 

1. The low-pressure gravity circulation is at present 
very much used in the steam heating of private houses, 
churches, and schools. Its principal merits, when well 
done, are : It is safe ; noiseless ; the temperature of the 
heating surface is low and uniform ; all the water of 
condensation is returned into the boiler, except a very 
small loss from the air-valves ; it is easy to keep the 
stuffing-boxes of the heater-valves tight ; and it is no 
more trouble to manage than a hot-water apparatus. 

There are four systems of low-pressure steam-piping, 
whose principal features are : 

1st. Main distributing pipes and distributing risers, 
with corresponding return mains and risers (see Fig. 1, 
at A). 

2d. Main distributing pipes and distributing risers, 
with a corresponding return main, and a separate return 
riser for every coil or heater ; the return risers not con- 

1 



2 STEAM HEATING FOR BUILDINGS. 

necting with each other until they are below the water- 
line (see Fig. 1, at B). 

3d. Main distributing pipes and distributing risers, 
with corresponding return mains and no return risers, 
the distributing riser carrying the water of condensa- 
tion back, through a relief, to the main return pipe on 
the floor of basement (see Fig. 1, at C). 

4th. (The single-pipe job, always a small one.) A 
single pipe for every heater, run directly from the top 
of the boiler to the heater, rising all the time in the 
direction of the heater, and of size sufficiently large 
that the steam passing to the heater, to supply the loss 
from condensation, will not interfere with the condensed 
water returning along the bottom of the pipe. 

System No. 1 can be run at any pressure, provided 
the pipes are sufficiently large in diameter and properly 
put up, and is the system commonly used in large 
buildings; not because it gives the very best results 
when the pressure is low, but because it gives ordi- 
narily good results and saves much pipe and labor. 

System "No. 2 should aliuays be used in private houses, 
and in buildings where extremely low pressure is em- 
ployed, as with this system a job can be made per- 
fectly noiseless, when done with care, and there is 
never any difficulty in expelling the air. 

Systems 3 and 4 are only employed in low-pressure 
heating, and when very large horizontal mains are 
used they give good results ; but are not to be recom- 
mended for large or complex jobs. 

For those not acquainted with the technical names of 
the different parts of the systems, and to prevent mis- 
conception of terms used, the following explanation is 
given : 



GRA VITY-CIRCULA TING APPARA TUS. 



NOMENCLATIVE. 

2. The same names always apply to the same part of 
the circulation, no matter what the system. The word 
circulation here means the whole distribution of pipe in 
any one job or apparatus. 

The Main Steam or Distributing Pipe. — The nearly 
horizontal live-steam main, generally near the cellar 
ceiling (a! a" a'"). 

The Main Return Pipe. — The nearly horizontal pipe 
on the floor, or thereabouts, of the cellar, for carrying 
the condensed water back to the boiler (b' b" b"). 

The Steam Riser. — The pipe that carries the steam 
from the main distributing pipe to the radiators (c 
c" c"). 

The Return Riser. — The pipe that carries the con- 
densed water from the radiators to the main return 
(d' d'). 

The Steam- Riser Connection. — The pipe that joins the 
main distributing pipe and steam riser (V e). 

The Return-Riser Connection. — The pipe that connects 
the return riser with the main return pipe on the floor, 
and which has one or more T's in it, below the water- 
line, — to receive the steam-riser relief (//). 

The Steam-Riser Relief. — The pipe that connects the 
bottom of the steam riser with a T, in the bottom of the 
return-riser connection, or main return pipe, below the 
water-line; to carry the water that runs down the steam 
riser into the return-riser connection or main return 

pipe (g g)- 

Main Relief Pipes. — Connections between the main 
steam and return pipes, to throw the water carried from 
the boiler, and that condensed in the main steam-pipe, 



4 STEAM HEATING FOB BUILDINGS. 

into the return main, also employed as an equalizer of 
pressure in the system (h). 

Radiator Connections. — The pipes which run from the 
risers to the radiators, both steam and return, usually 
no longer than is necessary to get spring enough for the 
expansion of the risers (i i i). 

A Relay.— The jumping up of a main steam-pipe, with 
a main relief at the lower corner. This is to admit of 
keeping the main steam-pipe near the line of the risers 
and the ceiling, and above the water-line, when the 
main lines are long (j). 

Pitch — Is the inclination given to any pipe, and in 




the steam maius of a low-pressure or gravity apparatus, 
it should be down and away from the boiler (except in 



GRAVITY-CIRCULATING APPARATUS. 5 

System No. 4), and, if possible, toward the boiler in 
the main return. (When the water and the steam run 
in the same direction through pipes, one source of noise 
is prevented.) 

3. Water-Line. — The general level of the water in the 
boiler and throughout the apparatus. In some cases, 
where the boilers are at a distance, or in a subcellar, and 
the fitter wishes to gain the advantages of having returns 
and reliefs coming together leloiv water, he makes an 
artificial water-line by raising the main return pipes 
higher than his connections before he drops to the 
boiler. It is also necessary to bring a relief from the 
main steam-pipe to this raised part of the return to 
prevent siphoning into the boiler. Fig. 2 shows how 
this should be done. 

It frequently happens in buildings where the line of 
the floor is below the water-line, that there are good 
reasons for not running the return pipe on the floor, 
when a modification of what is shown in Fig. 2 may be 
used ; the return pipe being hung from the same hang- 
ers as the steam-main, and immediately below it, but 
raised about as shown before being dropped to the floor 
at the first favorable position. Still another modifica- 
tion is to trap each return riser with an inverted water 
siphon by running the return riser five or six inches 
below the main return pipe, then rising and connect- 
ing with it. When any of these means have to be re- 
sorted to, it would be well to have a pet-cock at their 
lowest points to draw the water from them in cold 
weather should they not be in constant use, as these 
water-traps might freeze. 



6 STEAM HEATING FOB BUILBIN08. 

HOW A BUILDING IS PIPED. 

4 The steam-fitter should commence his work in a 
new building at an early period of its construction ; and 
architects and parties paying for the work should see 
that the contract for steam heating be let when the 
mason and carpenter work is let. 

The risers are the first work done in a new building 
constructed in the ordinary way. If the builder and 
steam-fitter have an understanding at the commence- 
ment of the work, the former can leave the proper re- 
cesses in the walls exactly where the steam-fitter wants 
them. This will save much work to the fitter, and pre- 
vent the mutilation of the walls, and be no expense to 
the mason. 

When the walls are up, the joists in their places, and 
the roof-boards or roof on, the steam-fitter should then 
put up his risers. 

If the building has not more than three floors to be 
heated, it will answer to rest the risers on a support at 
the bottom of the recess ; but in higher buildings the 
risers should be suspended by the middle, so that the 
expansion may be divided. By allowing the riser to go 
both up and down from the middle, the steam-fitter will 
be able to get along with shorter radiator connections, 
and will avoid the deep cutting of the floor joists. 

5. The steam-fitter should avoid, as much as possible, 
taking two heaters from the same steam connection on a 
floor, and if it be unavoidable, he should drop his re- 
turns down, and bring them into the return riser some 
distance apart ; or, better still, he should run them 
separately down below the water-line (System No. 2), as it 
will prevent one heater from taking the air from the others. 



GRAVITY-CIRCULATING APPARATUS. 7 

6. If the risers are on the side of the room, so that 
their outlets come between the joists, it is best to keep 
the T's about half-way between the laths and the flooring, 
as this admits of nippling up, and leaves room for cross- 
ing the pipes, if required, below the floor. But if the 
outlets come at the side of the joists, care must be taken 
that the T's come in the exact, place. In a building with 
the risers resting on the bottom, and all the expansion 
upward, the top outlet must be the greatest distance 
below the top of the joist, but it must never come within 
f of an inch of the floor when expanded to the ut- 
most; so also with the rest ot the T's, according to their 
distance from the bottom of the riser. 

7. With low-pressure steam, the steam risers should 
be large. The general practice with steam-heaters is to 
reduce one size of pipe for each floor. This rule is not 
arbitrary ; but as architects' specifications usually call 
for it,' there are no objections, provided the -piipe is large 
enough. 

In System No. 1 the return riser is generally one size 
smaller than the steam riser, but it should never be 
smaller than J of an inch pipe. 

In System No. 2, where many return risers are 
brought down in the same place, a 1-inch pipe for large 
heaters, and a 5-inch pipe for small ones, are the usual 
sizes. 

When the risers' are in, the outlets should be plugged 
up with pieces of pipe a foot or so in length, instead of 
the ordinary plug, as the latter is often difficult to get 
out when the plastering is done. 

The risers should then be tested with cold water to 
from 100 to 200 pounds per square inch ; this will show 
if there are any cracked fittings or split pipe, and will 



8 STEAM HEATING FOB BUILDINGS. 

save much time and annoyance when steam is gotten 
up. 

When automatic air-valves are to be used on the steam- 
heaters, a f-inch pipe should be run in the riser recess, 
with an outlet at each floor to receive the air-valve 
connection. The lower end of this air and vapor pipe 
should be taken to the nearest sewer, outside of the seiver 
traps. 

8. At this stage of the work, and before the floors are 
laid, the radiator connections should be run, and firmly 
fastened in their places, making due allowance for the 
thickness of the furring on the walls, for the plastering, 
and for the baseboard. The radiator connections are 
usually run 1 inch or lj-inch for the steam connection, 
with a corresponding | or 1 inch pipe for the return, 
according to the size of the heater ; 11-inch steam-pipe 
being enough for a direct radiator of 150 square feet 
of heating surface, at low pressure, ivitli a main of 
sufficient size. 

"When the radiator valves are threaded right-handed, 
the elbows on the ends of the connections may be left- 
handed, to admit of connecting, by a right-and-left-hand 
nipple below the valve, and between the valve and elbow, 
or vice versa. 

When both valves are at the same end of the radiator, 
it is better to have the right and left nipples between 
the valves and the radiator. With this arrangement 
both valves of the radiator can be connected simultane- 
ously, and the movement of the radiator will be in the 
direction of the valves. It also admits of the discon- 
nection of a heater after simply closing the radiator 
valves. 

When the radiators are to be connected by any of the 



GRAVITY-CIRCULATING APPARATUS. 9 

foregoing plans, the connections can be firmly fastened 
(but not confined at their ends), so they may come in 
their exact places through the floors. The free ends of 
the connections should be closed with pieces of pipe 
long enough to come above the floors when laid. The 
air-pipe should also be run at the same time, and 
brought through the floor in close proximity to the 
position the air-valve will occupy on the heater. 

At this stage of the work the steam-heater usually 
waits until the floors are laid, plastering done, partitions 
set, and the basement graded. 

9. Steam Mains. — Nearly all the success of the ap- 
paratus depends on its steam mains, their sizes, and how 
they are run. 

A job has never yet been spoiled by having its steam mains 
large; still, there should be a limit to their size, to 
prevent unnecessary expense, and to keep the con- 
densation and radiation of the distributing pipes at a 
minimum consistent with the actual requirements of 
the heating surfaces. 

The size of steam mains depends on the pressure of 
steam to be used, the distance it is to be carried, the 
temperature of the exposure of the heating surfaces, 
and their extent. But as it is not my intention here to 
speak of steam used expansively, I shall endeavor to 
give sizes only for direct return, or gravity-circulation 
apparatus. 

Gravity-circulation apparatus are of two kinds, low 
and high pressure. The low-pressure apparatus de- 
pends for a circulation on the difference of level of 
water in the return risers and the boiler, irrespective 
of the steam pressure at any part of the distributing 
pipes ; but the maximum pressure of steam to be car- 



10 STEAM HEATING FOB BUILDINGS. 

ried must never exceed the equivalent of a difference 
in level of water between the water-line of the boiler 
and the lowest part of the distributing main. 

There is another condition under which this system 
will work, and that is, an increase of pressure sufficient 
to nearly establish an initial pressure • throughout the 
apparatus ; but the difference in pressure at any part of 
the apparatus must not exceed the equivalent of a head 
of water between the water-line in the boiler and the 
lower part of the steam main. It is then a high-press- 
ure gravity circulation. 

A well-arranged gravity circulation should be made 
to work at any pressure; for with its heating surface 
properly proportioned it can be made to meet the exi- 
gencies of fall, winter, or spring weather, by simply 
carrying a pressure suitable to the occasion. 

10. To have the water of condensation return directly 
into the boiler, under all conditions of pressure, the 
main pipes must be large enough to maintain the pressure of 
the boiler, to within one pound, in every part of the appa- 
ratus, and the water-line of the boiler should be not 
less than 4 feet from the bottom of the horizontal 
distributing mains at their lowest part ; and that dis- 
tance will only answer in short mains, such as those 
used in the generality of city business buildings and 
blocks. In large public buildings and others, having 
their boilers in out-houses, the difference between the 
boiler line and the mains should be all it is possible to 
get. 

11. A main should not decrease in size according to 
the area of its branches, but very much slower, and 
should be rated by the heating surface and the distance 
it is to be carried. Neither should the main at the 



GRAVITY-CIRCULATING APPARATUS. \\ 

boiler be equal to the aggregate size of all its branches 
— an expression very much in vogue in specifications 
for steam heating. 

Mains which have given the best results leave the 
boiler of sufficient size (calculated from practical re- 
sults), and are reduced very slowly, if at all, until very 
near the end. 

The area of the cross section of a 1-inch steam-pipe 
is taken as unity, for the sake of easy calculation, in the 
rating of steam-pipes, and the area of a 1-inch pipe in the 
main, at the boiler, to each 100 square feet of heating sur- 
face, mains included, is deduced, from the size of the 
mains and heating surfaces of some of the best heated 
buildings in the United States, and has been the writer's 
rule for some years. 

12. When the main steam-pipe leaves the boiler, it 
should, if possible, be carried high at once, and have 
the stop-valve at the highest part in the pipe, so that 
condensed water cannot lodge at either side of it when 
shut. This will prevent cracking at this part of the 
pipes when the valve is opened. If this arrangement 
cannot be carried out, and the valve has to be nippled 
on the dome of the boiler, or if there are several boilers, 
and they have to be made interchangeable with regard 
to their use, there should be a relief of large size in the 
main, just outside the valves. 

13. It is well to mention here that a relief which 
leaves the steam-pipe must be brought into the return 
pipe in a position corresponding exactly to where it 
leaves the main ; that is, when it comes from the out- 
side of the main stop-valve, it should be taken to the 
outside of the main return valve. Otherwise, if an at- 
tempt is made to shut off, and both valves are closed, 



12 STEAM HEATING FOR BUILDINGS. 

the water will back up and fill the apparatus. So, also, 
with all branches, risers or connections ; if there is a 
valve in the steam part, tliere must also be one in the re- 
turn, and reliefs must leave the steam-pipe and enter the 
return on corresponding sides of the respective valves. 

14. From the highest point the main steam-pipe 
should drop slowly, as it recedes from the boiler (£ inch 
to 10 feet being a fair pitch), that the course of the 
steam and the water may be in the same direction. 

A main stesfm-pipe should not run very close to the 
wall up which the risers go. There should be room 
enough for a riser connection (2 or 3 feet), and when 
the mains are long, and the expansion great, the dis- 
tance should be increased. 

15. The T's in the main, for the riser connections, are 
better turned up than sidewise, as by nippling an elbow 
to them you can get any desired angle, and should the 
measurement for the main be a little incorrect, it will 
make no difference. This arangement also makes a 
good expansion joint, if the mains have much travel. 

Where the pipe reduces in size, it is well to put a re- 
lief in the lower side of the reducing fitting, as the water 
that is pocketed there, by the large pipe pitching in the 
direction of the smaller one, may be the cause of crack- 
ing and noise in the pipe. Some steam-heaters use an 
eccentric fitting in reducing, which brings the bottom 
of the pipes on the same line and makes nice work. 

16. When it is necessary to have stop-valves to the 
risers, the steam-fitter often places them in the riser 
connections, with a valve also in the riser relief. This 
arrangement requires three valves, and also stops the 
local circulation and equalization of pressure when they 
are closed. 



GRA VITY-CIRG ULA TING APPARA TUS. 



13 



It is better to use only two valves, one to the steam 
and one to the return riser, and place them a few inches 
up the riser, above the riser connection, which brings 
them also above the steam-riser relief, saving a valve 
and lessening the chances for noise in the pipes. 

In System No. 2, where the returns are carried down 
separately, and collected together below the water-line, 
the return valve should be below all such connections, 
and the steam-riser relief should have a separate con- 
nection with the main return, and have no valve. 
Straightway valves are best for risers. 

The extreme end of a steam main should be con- 
nected by a relief with the main return, being in fact, a 
continuation of the main down and into the return. 

17. Stop-valves in main steam-pipes are either globe, 




angle, or straightway. When a globe valve is used, it 
should be turned with its stem nearly horizontal, as 



14 STEAM HEATING FOE BUILDINGS. 

shown in Fig. 3. The reason for this is obvious, when 
we consider that the water of condensation in any pipe 
runs along the bottom of it. "When a globe valve is 
turned up, as in Fig. 4, the water in the pipe has to half 
fill it, before it flows over the valve seat, to pass along 
in the pipe. But, when the valve is on its side, it is 
different, for then the side of the opening of the valve seat 
is as low as the bottom of the pipe. 

Neither should the stem of any valve be quite hori- 
zontal when it can be avoided. It should be raised 
enough (10 degrees) to prevent water from collecting in 
the threads of the nut and stem, and being forced out, 
by the pressure of the steam, through the stuffing-box ; 
which makes a constant dropping of water, that it is 
almost impossible to hold with ordinary packing. But 
with dry steam it can be held. 

Globe or angle valves should be so turned in a heat- 
ing apparatus that by simply closing the valve to be 
pacJced } and its corresponding valve in the return, or vice 
versa, and waiting for the steam to cool down, the stuff- 
ing-box or gland can be removed without the escape of 
steam. To do this it is necessary to have the pressure 
side of every pair of valves turned toward the boiler. 
By the pressure side of a valve is meant the under side * 
of the disk. 

18. Main Betum Pipes. — In small apparatus (up to 3- 
inch steam-pipe) they are usually run one or two sizes 
smaller than the corresponding steam-pipe. 

In returns which are below the water-line, or are 
trapped to give them an artificial water-line, and conse- 
quently always full of water, there are no currents but 
the flow of the water toward the boiler. This style of 
return admits of the smallest piping, but good practice 



GRAVITY-CIRCULATING APPARATUS 15 

has placed it at one quarter of the area of the steam- 
pipe, for all conditions, for apparatus with larger than 
a 3-inch steam-pipe. 

In apparatus with less than 3-inch pipe, the return 
is usually only one size smaller than the steam-pipe, 
that it may have a practical magnitude, and thus avoid 
the possibility of getting it stopped with the dirt or sedi- 
ment carried to an elbow with the current of the water. 

19. In dry returns — L e., which have no water-line — 
there are local currents, often going in contrary direc- 
tions, the water gravitating toward the boiler, the steam 
flowing to the heaters, and the air — the greatest source of 
annoyance to the steam-heater — going to every place except 
out of the air-valve. This style of return is not much 
used, but in cases where there is no basement it can- 
not always be avoided. 

One-half the area of the steam-pipe has been found, 
in practice, to give good results in dry return pipes. 

20. Check-valves are generally used in return pipes 
where they enter the boiler. Some steam-heaters leave 
them out on account of the back pressure they cause 
to the return water ; but the practice is very much to be 
condemned when two or more boilers are connected, 
as an inequality in draught, or the cleaning of a fire, 
will make a small difference of pressure between boilers, 
causing the water to run from one boiler to another 
through the return pipes. 

Check-valves of large area in the opening, with a 
small bearing on the seat, can be made that will not 
give more than one eighth of a pound back pressure. If 
the valve is not ground, and cleaned frequently, when 
the job is new, there will be nothing but the actual 
weight of the disk to overcome.* 

* Swing "check valves" are now in use which give practically no 



16 STEAM HEATING FOB BUILDINGS. 

It is sometimes convenient to reduce a return pipe 
where it enters the boiler for a short distance. This 
may be done to a limited extent, bearing in mind the 
actual quantity of water to be admitted to the boiler in 
a given time. 

Extra strong pipe and fittings should be used in all 
returns and feed-pipes, from where they are tapped into 
the boiler, to outside the brickwork ; and when they are 
exposed to the action of the fire it is well to cover them 
with a " slip tube" made of a larger size, ordinary steam 
pipe. 

resistance to the flow of return water, and are preferable to "poppet 
checks " when there is no pulsation, only a steady flow. 



CHAPTEE n. 

RADIATORS AND HEATING SURFACES. 

21. All radiators — box coils, flat coils, plate or pipe 
surfaces, arranged to warm the air of buildings — are 
heating surfaces. 

The vertical tube radiator is now the accepted type 
of a first-class heater, and nearly all manufacturers have 
their own peculiar style, with varying results as to ef- 
ficiency. The steam-fitter or purchaser should use 
great caution in the selection of radiators. 

The common return-bend radiator, Plate I., Fig. 1, is 
the most widely manufactured ; it is not patented, and 
is second to no other vertical tube-heater. 

The construction is simple ; a base of cast-iron, A, be- 
ing simply a box, without diaphragms, with the upper 
side full of holes, about 2 j inches from center to center, 
tapped right-handed ; a pipe, B, for every hole, 2 feet 
6 inches or 3 feet long, threaded right and left handed, 
and half as many return bends, C, as there are pipes 
tapped left-handed. 

The manner of putting these heaters together is to 

catch the right-handed thread of two pipes one turn in 

the base, then apply the bend to the upper and left 

threads of the same two pipes, and screw them up simul- 

2 17 



18 STEAM HEATING FOR BUILDINGS. 

taneously with a pair of tongs on each pipe, while a 
second person holds the bend with a wrench made for 
the purpose. 

Steam-fitters who buy bases, and make only a few 
radiators, to keep the boys at work when in the shop, 
should count each set of threads in ; but they who make 
for the trade gauge their threads and pipes, so as to 
always enter the base first. If the pair of pipes in any 
one bend are not plumb, screw the pipe at the side from 
which they lean a little tighter, which will shorten that 
side and draw the bend over. 

22. I will here explain the action of steam entering a 
radiator, as nearly all the patents on the so-called posi- 
tive circulating radiators are to facilitate the expulsion 
of the air and the admission of steam. 

The general impression among steam-fitters is, that 
when steam enters a radiator the air is backed up and 
confined in the top of the pipe ; and it will be, when the 
pipe is single and closed at the top, without any of the 
usual means to get it down, although steam is not 
quite one-half the weight of air, which may seem an 
anomaly to the scientific engineer. 

When two pipes are connected at the top with a bend, 
or when there is an inside circulating pipe, or diaphragm 
of sheet-iron slipped into it, the air immediately gives 
way and falls in the pipes nearest the inlet first ; but 
should there be no air-valve on the radiator, the air will 
be crowded at first to the further end of the radiator, 
and should the system be a gravity circulation, without 
an outlet to the atmosphere, it will remain in the radia- 
tor, impairing its efficiency and often deceiving the no- 
vice, as it in time heats by contact with the steam ; but 
when there is a thumb-cock or air-valve on the radia- 



RADIATORS AND HEATING SURFACES. 19 

tor, usually on the furthermost pipe from the inlet, the 
result is quite different. In the common return-bend 
radiator and others of good construction the action is 
direct, and the pipes heat consecutively, excepting, per- 
haps, the pipe the air-valve is on, and a few near it, 
which sometimes heat ahead of their order, on account 
of the draught of the air- valve. 

Thus, when the steam enters a well-constructed radia- 
tor, the air falls to the base, and is driven out at the air- 
valve, the pipe of which may be run down inside the 
base (as is seen at D, Fig. 1), which will bring it into 
the lower stratum, drawing it off to the last. 

This is the most simple test for a good heater. Any 
kind of radiator that nearly always has a few cold pipes, 
sometimes in one part of the heater, and sometimes in 
another, should be avoided. 

Fig. 2 shows a device (patented) for making a return- 
bend radiator positive. The pockets A A, filling with 
condensed water, makes a seal which at times prevents 
the flow of steam along the base and forces it in a con- 
tinuous stream through the pipes (see arrows in cut). 

Figs. 3 and 4 show cross section of modifications of 
positive return-bend radiators. Fig. 3 can be used as 
a vertical radiator only, but Fig. 4 can be used in 
any position from perpendicular to horizontal, as seen 
at Figs. 5 and 6, and is peculiarly adapted to indirect 
heating. 

Single-tube radiators, welded or closed at the top 
with a cap, with an inside circulating device, are also 
much used ; some of them compare favorably with the 
return-bend radiator, but are slower in heating. 

Fig. 7 shows the first of this class put on the market. 
A is the cast-iron base, B the welded tube, and C the 



20 STEAM HEATING FOR BUILDING 8. 

septum of wrought iron slipped inside the tube and 
projecting an inch into the base. This heater depends 
on the gravity of the air for a circulation. 

Tig. 8 shows another heater of this class which is 
positive in its action. A, cast-iron base ; B, diaphragm 
cast in base ; C, welded tube ; D, inside tube, open top 
and bottom, and screwed into the diaphragm. The 
action of the steam can be seen by the arrows. 

Fig. 9 shows a fire-bent tube radiator very positive in 
its action. 

23. Cast-iron radiators are of two kinds, plane and ex- 
tended surfaces. 

Plane surfaces, as the trade understands them, may 
be either flat, round, or corrugated, provided the coring 
or inside surface of the iron corresponds and follows 
the indentations of the outside, as in Fig. 10, and in all 
wrought-iron heaters. Extended surface is understood 
when the outside surface of the heater is finned, corru- 
gated, or serrated, with the inside straight, as in Fig. 11. 

For direct radiation, where the heater is placed in the 
room, nothing is gained to the unit of value by having 
the surface of the heater extended, and a steam-fitter, in 
calculating the extent of his heating surfaces, should not 
take into consideration the whole outside surface of such 
a heater. It always has a value per square foot which 
is less than unity, varying with the different kinds. 

For indirect heating (the coil being under the floor or 
in a flue) the result is a little different as compared with 
shallow plane surface coils, where the air cannot stay 
long enough in contact with them to get thoroughly 
warmed, but presses into the room without hindrance. 
In this case the extended surface gives a better result, 
not because a square foot of the surface can transmit as 



RADIATORS AND HEATING SURFACES. 21 

much heat in the same time, but because it hinders the 
direct passage of the air, holding it longer in contact 
and preventing stratification. 

The cast-iron vertical tube radiator is a quick heater, 
the large size of the tubes causing chambers large in 
size and few in number, thus expediting the expulsion 
of the air. 

Fig. 12 shows a stack of cast-iron extended-surface 
radiators for indirect heating. 

24 Sheet-iron radiators are used in very low-pressure 
heating, the commonest form of which is the flat Bussia- 
iron heater, seamed at the edges and studded or stayed 
in the middle, with a space of about § of an inch be- 
tween the sides. They are used in a one-pipe job. 

COILS. 

25. Coils are always made of wrought-iron steam-pipe 
and fittings, and though not considered an ornament are 
first-class and cheap heaters. 

Fig. 13 shows a flat coil, which is a continuous pipe, 
connected with return bends at the ends, and strapped 
with flat iron, and is a very positive heater. 

Fig. 14 shows a miter or wall coil. It is composed 
of headers or manifolds, A A ; steam-pipes, B ; elbows, 
C ; and hook plates, D. 

There are many modifications of this coil, but one in- 
dispensable point in the making of it is, it must turn a 
corner of the room, or miter up on the wall. The pieces 
from the elbows to the upper header are called spring 
pieces ; they are screwed in right and left, and are the 
last of the coil to be put together. 

If a coil is put together, straight between two headers, 



22 STEAM HEATING FOB BUILDINGS. 

as seen at Fig. 15, it will be like Fig. 16 when heated, 
and cannot be kept tight for a single day ; the expansion 
of the first pipe to heat, being a powerful purchase to 
force the headers asunder, and when it cannot do so it 
will spring them sidewise. 

TO ESTIMATE THE AMOUNT OF HEATING SURFACE NECESSARY 
TO MAINTAIN THE HEAT OF THE AIR OF INCLOSED SPACE 
LN BUILDINGS TO THE DESIRED TEMPERATUEE. 

26. The ordinary rule-of-thumb way, of the average 
pipe fitter, is, to multiply the length by the breadth of a room, 
and the result by the lieight, then cut off two figures, from the 
right hand side, and call the remainder, square feet of heat- 
ing surface, with an addition of from 15 to 30 per cent, 
for exposed or corner rooms. 

In computing heating surfaces, there is much more to 
be considered, and it is evident, the amount of surface 
necessary for a good and well constructed building, will 
not be enough for a cheap and poorly put up one. 

The cubical contents of a room, occupy only an in- 
ferior place, when estimating for large rooms and 
halls, and no place at all, in figuring for small or ordi- 
nary office rooms or residences, which are heated from 
day to day throughout the winter. 

In a small room, on the second floor of a three story 
building, with only one outside wall, no windows, and 
the whole furred, lathed, and plastered, while all the 
other rooms of the building are heated, and maintained 
to 70° Fahr. place a portable heater, and keep it there 
until the room is heated to 70° also, then remove it. 
How long will it take to cool 10°? .Answer, perhaps 
two hours. Now make a window without blinds, and 
you find it cools 10° in less than half the time. Why ? 



RADIATORS AND HEATING SURFACES. 23 

Because the glass of the window, being a good trans- 
mitter of heat, it is able to cool more air than the whole 
outside wall. You may now say : What about the in- 
side walls and floors ? Why, they actually help to 
maintain the heat in the room by conduction, etc., from 
the other rooms. 

Thus, the windows are the Jirst and most considerable 
item. Secondly, consider the outside walls and how 
they are plastered — whether on the hard walls, or on 
lath and furring. Thirdly, the prospect — whether ex- 
posed or sheltered. Fourthly, whether the whole house 
is to be heated, or only part of it ? and, lastly, what the 
building is to be used for. 

TABLE OF POWER OF TRANSMITTING HEAT OF VARIOUS BUILD- 
ING SUBSTANCES, COMPARED WITH EACH OTHER. 

Window glass 1,000 

Oak and walnut 66 

White pine 80 

Pitch pine 100 

Lath and plaster 75 to 100 

Common brick (rough) 200 to 250 

Common brick (whitewashed) 200 

Granite or slate 250 

Sheet iron 1,030 to 1,110 

In figuring wall surface, etc., multiply the superficial 
area of the wall in square feet, by the number opposite 
the substance in the table, and divide by 1,000 (the 
value of glass), the product is the equivalent of so many 
square feet of glass in cooling power, and may be added 
to the window surface and treated in the same way. 

The following method has given good results, and is 
not wholly empirical. The writer has used it for many 
years in preference to any other : 



24 STEAM HEATING FOB BUILDINGS. 

Divide the difference in temperature^ between that at tvhich 
the room is to be kept, and the coldest outside atmosphere, by 
the difference, betiueen the temperature of the steam pipes, and 
that at which you wish to keep the room, and the product 
will be the square feet, or fraction thereof, of plate or pipe 
surface to each square foot of glass, or its equivalent in ivall 
surface. 

Thus : Temperature of room, 70° ; less temperature 
outside, 0° ; difference 70°. Again : Temperature of 
steam pipe, 212° ; less temperature of room, 70° ; differ- 
ence, 142°. Thus : 142 --70 = 0.493, or about one half a 
square foot of heating surface, to each square foot of 
glass, or its equivalent. 

It must be distinctly understood that the extent of 
heating surface found in this way, offsets only the win- 
dows and other cooling surfaces it is figured against ; 
and does not provide for cold air admitted around loose 
windows, or between the boarding of poorly constructed 
wooden houses. These latter conditions, when they 
exist, must be provided for separately. 

27. In isolated buildings, exposed to prevailing north 
or west winds, there should be a generous addition of 
the heating surfaces of the rooms on the exposed sides, 
and it would be well to have an auxiliary heater, to pre- 
vent over-heating in moderate weather. 

In windy weather it is well known to the observant, 
that the air presses in through every crack and crevice 
on the windward side of the house ; and should they 
take a candle, and go to the other side of the house, 
they will find that the flame of the candle will press out 
through some of the openings. Thus the air in a house, 
blows in the same general direction as the wind outside, 
and forces the warmed air to the leeward side of the 



RADIATORS AND HEATING SURFACES. 25 

house ; this is why the sheltered side of a house is often 
warmer in windy weather than in ordinary cold weather. 

Simple conditions, which tend to the warmth of a 
house, in windy and cold weather, without stopping the 
leakage of air, under doors or around windows are : 1st, 
blinds on the windows inside ; 2d, blinds on the win- 
dows outside ; 3d, window shades and curtains ; and, 
papered walls. The leakages are really blessings in 
disguise, in houses which are not systematically venti- 
lated. 

In buildings where the heating surfaces have proved 
slightly insufficient, double sashes in the windows have 
served to raise the heat to the required standard. 

In green-houses the saving of heat, when double 
glass sashes are used, is very apparent ; and in build- 
ings warmed altogether with direct-radiation (where 
no air is changed by flues, etc.), i to i less surface will 
do. But when the system is indirect, the saving is not 
so great, as the heat lost by ventilating will be the 
same ; the saving being proportional to the amount 
of air only, which would be cooled through the single 
glass. 



CHAPTEE IH 

CLASSES OF RADIATION. 

Heating surfaces are divided into three classes : 1st, 
direct radiation ; 2d, indirect radiation ; and 3d, direct- 
indirect radiation. 

28. Direct radiating surfaces embrace all heaters placed 
within a room or building to warm the air, and are not 
directly connected with a system of ventilation. 

The best place in a room to put a radiator, is where 
the moist air is cooled — namely, before or under the 
windows, or on the outside walls. "When the heater is 
a vertical tube radiator, or a short coil, which can oc- 
cupy only the space of one window, and when, as often 
occurs in corner rooms, there are three windows, the 
riser should be so placed as to bring the line of radia- 
tors in front of, and under the windows where they will 
do the most good — as the middle window. It is better 
still, when a small extra cost is not considered, to use 
two heaters, and place one in front of each extreme win- 
dow. 

When the room is large, and has many windows, the 
heating surface should be divided into as many parts as 
there are windows ; or, if the occupants object to so 
many windows being partly obstructed, divide into half 
as many parts, and distribute accordingly. 



CLASSES OF RADIATION. 27 

In schools or buildings with many windows, where 
children or persons cannot change their positions, but have 
to remain seated for several hours at a time, care must 
be taken that the heating surface is very evenly dis- 
tributed. A coil run the whole length of the outside 
wall is best, but if any kind of short heaters are used, 
every window should have its quota. Should a single 
window be left unprovided for, it will be found by ex- 
periment that a cold current of air will fall down in 
front of such window, and flow along the floor, in the 
direction of the nearest heaters, and cause cold feet to 
any who are in the line of its passage. 

The natural currents in a room with the outside at- 
mosphere the coldest, are doivn the windows and out- 
side walls, and up at the center or rear walls. This 
downward and cold current, should be met by the heated 
and upward current from the radiator, and reversed and 
broken up, as much as possible. 

29. Indirect radiation embraces all heating surfaces 
placed outside the rooms to be heated, and can only be 
used in connection with some system of ventilation. 

There are two distinct modifications of indirect radia- 
tion. One, where all the heating surface is placed in a 
chamber, and the warmed air distributed through air 
ducts, and impelled by a fan in the inlet or cold air 
duct. The other, where the heating surface is divided 
into many parts, and placed near the lower ends of verti- 
cal flues, leading to the rooms to be heated. 

The first of this class — namely, chamber-heat — has not 
proved a great success, and architects and steam heat- 
ing engineers are likely to have very little to do with it, 
as it has been found, that' in windy weather it is almost 
impossible to force air to the side of a building against 



28 STEAM HEATING FOB BUILDINGS. 

which the wind blows. The second of this class does 
well, as it admits of taking advantage of the force 
of the wind, to aid in bringing the warmed air into the 
rooms. 

In estimating the heating surface for low pressure in- 
direct radiation, it is well to nearly double what would 
be used for direct radiation. 

30. The indirect heater is usually boxed, either in 
wood lined with tin, or in sheet metal. The former is 
best when the cellar is to be kept cool, as there is a 
greater loss by radiation and conduction through metal 
cases ; otherwise metal is best, as it will not crack, and 
when put together with small bolts can be removed to 
make repairs, without damage. 

31. The vertical air ducts are usually rectangular tin 
flues built into the wall when the building is going up ; 
sometimes they are only plastered ; but round, smooth 
metal linings with close joints give much the best re- 
sults. The cross section of an air duct should be com- 
paratively large, as a large volume of warmed air, with 
a slow velocity, gives the best result. 

There should be a separate vertical air duct for every 
outlet or register. In branched vertical air ducts, one is 
generally a failure. 

The heated air from one heater, may be taken to two or 
more vertical air ducts, when they start directly over it ; 
but one should not be taken from the top, and the other 
from the side or the latter will be a total failure, unless 
the room to which the flue runs is exhausted ; i. e., the 
cold or vitiated air of the room is drawn out by a heated 
flue or otherwise. 

Inlet or cold air ducts are best, when there is one for 
every coil or heater ; and its mouth, or outer end, should 



CLASSES OF RADIATION. 29 

face the same way as the room to be heated. By this 
means, when the wind blows against that side of the 
house, the pressure is into the cold air duct, and 
materially assists the rarefied column of air, in the ver- 
tical duct, to force its way into the room. 

Often the steam-heater uses only one large branched 
cold air duct ; but this system will give trouble unless 
all the rooms are exhausted. 

The steam-heater should not take a job of indirect 
heating unless the building has been arranged especially 
for it, with some efficient system of flues, sufficient to 
change the entire air in a given time, not to exceed one 
hour. 

Frequently, the architect makes no provision for draw- 
ing out the cold or depreciated air, other than an open 
fire-place, and often they make no outlet. Such a room 
as the latter cannot be warmed by indirect heating at all. 
But when there is a chimney, or an unwarmed outlet or 
foul air flue, the heated column of air in the vertical hot 
air flue, is generally sufficient to force its way through. 
Very large rooms, with high ceilings, are difficult to 
warm by indirect heating alone. 

A cheap and good way to draw, or exhaust, outlet or 
foul air flues, is to connect them all to one large annu- 
lar flue, around the boiler chimney flue. 

Warmed fresh air flues should be in, or near the out- 
side walls, and should discharge near the windows ; and 
foul air flues should be in the inner walls, and have an 
opening near the floor and ceiling, with register valves, 
to allow the occupant to use either, or both, as he thinks 
proper. 



30 STEAM HEATING FOR BUILDINGS. 

32. To find the time in minutes, it will take for a room 
of known cubical contents, to change its air through a 
flue of one square foot cross section : Multiply the 
velocity of the air through the flue in feet per second, 
by 60, and divide the cubical contents of the room in feet 
by the result. Thus : Velocity of air 5 feet x 60= 300 
-=-into cubical contents, say, 4,000=13.3 minutes. 

To find the time for other sized flues, multiply this re- 
sult by the cross section of flues, in square feet, or frac- 
tions thereof. 

The velocity of the air in heating flues with only a 
natural draught, rarely reaches 8 feet per second, no 
matter what the conditions ; and 2 feet, 4.5 feet, and 5.2 
feet respectively, are fair averages of velocities for first, 
second, and third floors of a house. 

33. Direct-indirect radiation embraces all heating 




surfaces placed within, or partly within, the room to be 
warmed, indirect connection with some system of ventilation. 
Heaters of this class are usually placed on- the out- 
side walls or under windows, following the same general 



CLASSES OF RADIATION. 



31 



rules as direct radiation, excepting the clusters are 
deeper, so as to prevent the cold air from rushing 
through without being warmed. 

Fig. 5 is a favorite modification of this style of heat- 
ing. It is a section of a room, showing the action of the 
currents of air. A A, outside wall ; J5, partition wall ; 
(7, radiator ; D, inlet flue ; E, damper or valve ; F, ven- 
tilating flue or foul air outlet ; G, fresh air mixing with 
the air of the room ; H, air of the room passing along 
the floor to the heater ; i, a percentage of the air in the 
room passing off by the ventilator. 

Fig. 6 is another modification of direct-indirect radia- 
tion, where some of the local heat is employed to exhaust 




or draw out the vitiated air of the room. The arrows 
show the action of the air currents. A is a section of a 
radiator built with a sheet-iron flue, B, between the 
tubes, and passing through a hole, cored in the base, 
which connects with the register in the floor, and a foul 
air flue in the wall. 

Some of the radiant heat, etc., from the radiator, A, 



32 STEAM HEATING FOR BUILDINGS. 

warms the sheet-iron flue, B, which in turn warms tho 
air within it, causing an acceleration of the current in 
the foul air flue, and consequently drawing an equal 
amount of fresh air in at the opening, C. 

In estimating heating surfaces, for direct-indirect 
heating, it is well to use once and a half as much as 
would be used for direct radiation alone. 

There is this further distinction between the three 
systems of radiation : Direct radiation warms only the 
air of the room and maintains the heat. Indirect heat- 
ing warms only the air that passes in, and cannot warm 
the same air twice, and consequently has to raise the 
temperature of all the air that passes, from the outside 
temperature, to that necessary to maintain the tempera- 
ture of the room, and make up for the loss by ventila- 
tion. Direct-indirect radiation warms part of the air 
over again, and warms all the air admitted for ventila- 
tion, which latter can be varied to suit the occupants. 

POSITION FOR INDIRECT HEATERS. 

34 "With indirect radiation, the heating apparatus 
being steam, a building cannot be other than sufficiently 
ventilated ; * but it frequently happens in large rooms, 
with very high ceilings, or large auditoriums, as 
churches, schools, theaters, or assembly rooms of any 
kind, that they are not always satisfactorily heated ; for 
it is difficult to warm them by indirect radiation alone, 
unless there is a heater to each register, and many reg- 
isters placed before the windows, supplemented by di- 
rect radiators, placed near doors or passages, through 
which there will be strong local currents. 

Heated air from a few large registers in a very large 

* This has been questioned, but the writer maintains for ordinary- 
purposes, that when the air is moved sufficiently often to keep the rooms 
warm, taking into consideration the low initial temperature of the air, 
that it is sufficient. 



CLASSES OF RADIATION. 33 

room, goes directly to the ceiling, and fills the room 
from above, expelling the same amount of air through 
the ventilators ; if the building had no windows, this 
would answer ; but as buildings have windows — which 
cool the air rapidly, there will be a falling of air, in 
front of the windows, which has not been pressed down, 
by the warm air above ; but has fallen of its own gravity, 
by losing its heat, from contact with the cooling surfaces 
of the building ; and these downward currents, having 
nothing to neutralize them, pass cold along the floor, in 
their passage to the ventilator, or to an ascending cur- 
rent of warm air — caused by the heat given off from the 
bodies and lungs of the audience. 

This is why people in churches and theaters suffer 
from cold legs and feet, and sometimes have a cold cur- 
rent on their heads, which makes the occupant certain — 
the window is open a little ; though a thermometer near 
by marks 70°, for the thermometer is not in the cold 
current. 

If a building must be heated entirely by indirect 
radiation (except where the occupants can change their 
position and draw down curtains, or close inside blinds), 
use as many heat registers as possible, and place them 
in front of the windows, or where a cold current is 
likely to come down. 

Usually in office rooms, and ordinary rooms in resi- 
dences, one register in the coldest part of the room can 
be made to answer ; but if the room is large, with many 
windows, more should be used. 

Figs. 7 and 8 are sketches of indirect radiators in 
position, showing a heater to each register. Fig. 7 be- 
ing for a lower floor, and Fig. 8 for upper floors ; where 
the air is carried through a flue in the wall. 
3 



34 



STEAM HEATING FOR BUILDINGS. 



Rooms warmed this way when they have a fire-place, 
or a ventilating flue of proper size in the inside wall, 




with sufficiently large heaters and registers before the 
windows, or in the outside walls, should never fail. 

35. It will be seen, that the dampers in the cold air 
inlets, are not automatically regulated. They are some- 
times so regulated, to prevent the freezing of the coils ; 
but when the steam and return pipes are sufficiently 
large, coils are seldom frozen ; for when steam is up, 



CLASSES OF RADIATION. 



35 



they cannot freeze, and when steam is not up, there is 
no water in the coils to freeze, for it has subsided to 
the water line. 

Only an apparatus with scant pipes and parts will 
freeze, unless the coil is too close to the water line, or 
partly below it. 

Indirect coils, if they have valves, should never be 
shut off in very cold weather. If the room is not to be 
heated, close the registers and inlet ducts. The closing, 
or partly closing of a valve, may freeze a coil, by inter- 
rupting the circulation. The closing of one valve, and 
the leaving open of the other, is sure to freeze a coil, if 
exposed to sufficient cold ; as in either case, it will fill 
with water. This applies to all radiators. 

Fig. 8 a, shows the Nason Indirect Kadiator arranged 
for hospitals, asylums, etc. It has a metal case and can 
be shut off in sections. 




Fig. 8 a. 



CHAPTEE IV. 

HEATING SURFACES OF BOILERS. 

36. The direct heating surface of a boiler (fire-box), 
lias a value, several times greater than the indirect sur- 
face (flues and tubes) ; but the shape of the furnace, its 
size, and the angle of the heating surface, as well as the 
length, size, and position of the flues, give a greater or 
less value to the indirect surface ; but these values are 
only comparative. 

In constructing boilers for heating apparatus, an effort 

should be made to have the greatest amount of direct 

J surface, with a minimum of indirect surface ; forjt is 

desirable to have slow combustion, with thick fires, 

and thus reduce the attendance to a minimum. 

When furnaces are comparatively small, with a high 
rate of combustion, flue surfaces may be lengthened 
with beneficial results ; but in a private house, with a 
self-feeding boiler (base-burner), or one which has a 
deep furnace, constructed to put in six to eight hours' 
coal, and keep steam uninterruptedly for that time, a 
great part of the heating surface should be in the fire- 
box ; the heat from the gases being comparatively low 
tempered, and the amount passed in a given time small. 

It would be well to say, that most writers on boilers, 

36 



HEATING SURFACES OF BOILERS. 37 

put too high a value on what is termed direct Jieating 
surface, in contradistinction to indirect or flue surface. 
Not that the value of a square foot of surface in a fire-box 
of ordinary construction has not 2 J to 4 times the value, 
for the same size of average tube surface, but they con- 
vey the idea, that by increasing surface, near, or in the 
fire-box, and decreasing the tube surface, near, or in the 
direction of the chimney in a threefold proportion, to 
the increase in the fire-box — they can evaporate as much 
water with the decreased surfaces. Below certain sizes 
and proportions (which have already been attained in 
boilers of ordinary good construction), this may be so, 
but when a fire-box or furnace is large enough for 
proper combustion, the surface of it is then receiving 
all the radiant heat there is, and by increasing the sur- 
face directly exposed to the action of the fire (beyond 
the required chamber for combustion), it will be neces- 
sary to have the surface of the fire-box as a whole, more 
remote from the fire ; as radiant heat from any source 
has its effect decreased, directly as the surface which ab- 
sorbs it. 

From a central point of heat, the rays diverge on all 
sides, and the intensity diminishes inversely as the square 
of the distance, which will be found to be directly as the 
surfaces of different sized spheres, which might surround it ; 
the value of the heating surface (for radiant heat), de- 
creasing for each unit of distance, in a geometrical pro- 
gression, whose ratio is 4 The above can be likened to 
the fire in an upright boiler ; assuming it has no down- 
ward radiation. 

In horizontal boilers, or boiler with long fire-boxes, 
or fired within horizontal cylindrical furnaces, the fire 
can be likened to a long column of heat, from which the 



38 STEAM HEATING FOR BUILDINGS. 

rays go off parallel to each other in the line of its length, 
but diverge in a line of its cross section ; which will 
give an inverse geometrical progression whose ratio is 2, 
as the decreased value of the surface, for each unit of 
distance it is removed from the fire ; but in any case, the 
assertion, that the intensity of radiant heat decreases 
directly as the surface which absorbs it, will hold good 
for any shape of fire, or any shape of furnace ; and that 
hanging tubes, projections, or corrugations in a fire- 
box, receive nothing from the radiant heat that would 
not be received by the plain surface ; so, although a 
person may take 4 foot of tube surface away, and add 
one foot to the fire-box, without perceiving they lost 
anything, yet they cannot, in a boiler that is already \ 
furnace, and \ flue, whose gases af combustion escape at 
a sufficiently low temperature, take away all the flues, 
or a large percentage of them, and by adding J of their 
surface to the fire-box, makes as much steam. 

37. All that can be gained by crowding the fire-box 
with surfaces, hanging or otherwise (which must not in- 
terfere with combustion), is, to reduce the bulk of the 
boiler ; the surfaces will be the same still, for the same 
work. It is therefore poor economy to reduce the size, 
when nothing else is gained, and make surfaces which 
will fill up on the inside with sediment, choke up in the 
tubes, or between them with soot and ash, and wear out 
in one-third of the ordinary time. 

It is an incontrovertible fact, that boilers with very 
small parts, require more surface for the same work 
done, than with large and plain parts ; because of the 
impossibility to thoroughly clean them, and the rapidity 
with which they choke ; the nearness of the tubes allow- 
ing the dirt to bridge between them. 



HEATING SURFACES OF BOILERS. 39 

A maximum of fire-box, with a minimum of flues, is 
proper, and should be the rule in house heating, where 
there is generally plenty of room in the cellar. 

38. If the surface of the fire-box be increased by pro- 
jections or corrugations, for the purpose of an increase 
of surface in contact with the highly heated gases of the 
furnace, the folds should be large and in vertical rows, 
so nothing can find a lodgment on them. 

39. The boilers which have given the best evapora- 
tive results, as well as the least trouble, and lasted the 
longest, have been the simplest, and the evaporative re- 
sults of a boiler depend more on the care with which 
they are kept clean, and the unimpeded circulation of 
the water within them, than on any peculiar disposition 
of the heating surface. 

Large boilers, compared to the work, are most eco- 
nomical ; but the limit is hard to fix, there are so many 
conditions to be taken into consideration, as well as 
styles of boilers ; and as it is really the size of the grate, 
and the velocity of the draft, compared to the work to 
be done (after the boiler is large enough), which regu- 
late the economy — hence a sufficiency of boiler, with 
the right grate surface, to burn the fuel, accomplish the 
most satisfactory results. 

A boiler that may do very well for the first year, may 
not give satisfaction the second year. Such will be the 
case with boilers barely sufficient for the work, which, 
while they are clean, and the person in charge of them 
has a pride in doing well, will pass muster ; but the 
second year, when the novelty has passed off, it will be 
quite different, then complaints will be heard, and one 
investigating steam apparatus with a view to putting it 
in his house, will be apt to reject it should he inquire 



40 STEAM HEATING FOR BUILDINGS. 

no farther. Then it is too late to assert — the trouble 
is known and can be easily remedied. 

40. In proportioning the size of boilers, all calcula- 
tions must be based on the supposition that the boiler 
will be neglected to a certain extent, and that there are 
parts of the best boilers which cannot be properly 
cleaned, and that all boilers deteriorate in transmissive 
power (the gravity return least of all, as the return 
water is pure) more rapidly at first, until a point is 
reached, where external deposits fall off, after which the 
impairment is slow, and caused only by slight deposits 
on the inside, chiefly oxides, which have a high trans- 
missive power themselves. 

41. Can a boiler, it may be asked, be robbed of its 
heat, by the gases of combustion, by retaining them too 
long in contact, in passing through long flues? Not if 
they are internal tubes or flues ; but there is a point be- 
yond which there is no gain. — namely, where the tem- 
perature of the gas and the steam becomes the same. 
Up to that point, the gases of combustion being the 
hotter, impart heat to the flue, but beyond it. neither 
the flue can impart heat to the gas, nor the gas to the 
flue, as they are of the same temperature. Boilers, 
when they are new, should have some such point, which 
simply moves nearer the chimney, as they become old 
and dirty. 

The rate of combustion will also give this point a 
variable position, for the time being. 

Some engineers think it preferable to let the gases of 
combustion escape at a higher temperature than the 
steam. In that case, the point can be assumed to rep- 
resent any constant difference of temperature of the gas, 
above the steam. 



HEATING SURFACES OF BOILERS. 41 

42. Keverberatory, or drop flues, in upright boilers, 
save much heat. A cause of loss of heat, in upright 
boilers (and possibly in many other boilers), which 
have a great many tubes, many more than the aggregate 
area of the chimney, is, the heated gases find the tubes 
directly over the fire, and pass out rapidly at a high 
heat, of their own gravity, leaving the gas in the outer 
rings of tubes inert, as may be seen in almost any up- 
right boiler, where the tubes of the outer circles are 
clogged with dirt ; the velocity of the draft, in the mid- 
dle tubes keeping them comparatively clean. But when 
there is a row of drop tubes, as shown in Fig. 14, or a 
flue built around the outside of the shell of the boiler, 
with brickwork, with the chimney flue leading from the 
bottom, as shown in Fig. 13, the gases are then drawn 
out, or " exhausted " by the heat in the chimney ; and 
the gases around the upper part of the boiler, become 
uniform in temperature, and stratify, the lowest being 
drawn off first, and the others following according to 
their temperature. 

When combustion is good, and the gases as they 
leave the boiler and enter the chimney flue, have not too 
high a temperature, the water icitliin such a holier has ab- 
sorbed all the available heat ; hence, to increase the sur- 
face of such a boiler, will not do much good, unless the 
grate surface is also increased ; since all the heat evolved 
has been absorbed. 

43. "Will the quantity of water within a boiler effect 
evaporation ? 

Many steam heaters and others, use boilers com- 
posed of very small parts, so as to have the greatest 
surface with the least water, with a view to evaporate 
more water in a given time, and cite the time between 



42 STEAM HEATING FOR BUILDINGS. 

starting the fire and the time steam is up, as a proof of it. 
This is a mistake ! The reason why steam is gotten up 
quicker, is because there is less water to heat to 212° 
before steam begins to make, but beyond that, the re- 
sult, with regard to steam making is the same, for the 
same surface, other things being equal. 

What is gained in first time, with sensitive boilers, is 
more than compensated for, in house heating, by having 
boilers which contain a large quantity of water, by keep- 
ing steam where a new fire is put in ; as boilers which 
contain small quantities of water are rapidly chilled, 
as well as rapidly heated, and must be fired often, and 
regularly. 

Fire engine boilers, require to be sensitive, and when 
much power, with small weight is a desideratum, they 
are all right. 



CHAPTEE V. 

BOILERS FOR HOUSE HEATING. 

44. Boilers for heating apparatus should have very 
few parts, and be as simple as it is possible to make 
them ; every part of them being constructed with a view 
to permanency ; and parts that wear out more rapidly, 
such as grates, should be so arranged that they can be 
renewed by the most inexperienced person. 

45. Requirements for house heating boilers are : 
1st. They should contain a quantity of water, suffi- 
ciently large to fill the pipes, and radiators, with steam, 
to any required pressure, without lowering the water 
enough in the holier to require an addition, when steam 
is up ; for should the steam go down suddenly, there 
will be too much water in the boiler. This occurs in 
boilers made with very small parts, or pipes, which 
have a small capacity, at the water line, and require 
great care ; for should the boiler have an automatic water 
feeder, set for the true water line, it will fill up, but 
cannot discharge again, when the steam goes down; 
while, if it has no feeder, there is danger of spoiling 
the boiler, as the water is in the pipes in the form of 
steam. 

For the quantity of water necessary to fill the pipes, 

43 



4A STEAM HEATING FOR BUILDINGS. 

with steam at any pressure, at a maximum density, see 
Table 29. 

2d. The fire-box should be of iron, with a water 
space around it, as in upright, or locomotive boilers ; 
to prevent clinkering on the sides, and the necessity of 
repairs to brickwork, which are unavoidable in brick 
furnaces. 

3d. The fire-box should be deep, below the fire door ; 
to admit of a thick fire, to last all night, and thus keep 
up steam. 

4th. The fire-box should be spacious, for the sake of 
good combustion. 

5th. The flues and tubes should be large, and in a 
vertical position, so they will not foul easily, and that 
any deposit would fall to the bottom. 

6th. The heating surface should be great in diameter, 
instead of in the direction of the chimney, and the last 
turn be a drop. 

7th. They should, if possible, be constructed of such 
shape and design, that they will require no sweeping, 
or cleaning, other than removing the ashes ; but when 
it is unavoidable, every facility should be made for 
easy access to such parts ; because they are often 
operated by inexperienced persons (house servants), 
who will condemn anything which gives trouble to 
them. 

8th. The fire-grate must be easy to clean (anti- 
clinker), and so designed, it will not crack or break 
when heated (see Grates, page 80). 

9th. The grate and ash-door must be so constructed, 
that a new grate can be put in quickly by any one. 

10th. There should be no tight dampers in the chim- 
ney flue, and when the flue goes out near the bottom 



BOILERS FOR HOUSE HEATING. 45 

(drop flue), it may be dispensed with altogether ; but 
the lire and draft-doors should be made to close air- 
tight (planed), so as to be capable of entirely damping 
the tire. This will prevent the possibility of coal gas 
escaping into the house ; the damping of a fire, by 
shutting off its supply of air, is the proper way ; for 
the draft of the chimney being unimpaired, draws all 
the harder on any crack, or crevice, in the brickwork, 
causing an inward current, which entirely precludes 
the escape of gas. 

11th. The perpendicular height of the boiler should 
not be too great for the cellar, so the water line will 
not be too near the level of the main pipes. 

12th. It should be so inclosed in brickwork as not to 
perceptibly raise the temperature of the cellar, in 
which it is, and have the whole outside of the boiler, 
heating surface, if required, by having either an up- 
ward or downward flue. 

"When upright boilers are constructed with drop 
tubes, as shown at a, Fig. 14, or with drop flues, as 
shown in Fig. 13, it is generally necessary to use a 
direct smoke pipe, as well as a bottom pipe, as shown, 
in which case an upper damper is required, and possi- 
bly it is better to have a lower damper also ; the two 
dampers should be connected at right angles to each 
other by a rod, as shown at i, Fig. 14, which prevents 
the possibility of having both dampers closed together. 

46. In upright boilers, for house heating, the propor- 
tion of fire-box to the flue surface admits of almost any 
modification, as the boiler can be made of large diam- 
eter, with short tubes and high fire-box drawn in at 
the bottom with dead plates, for the desired size of 
grate, or drawn in as shown in Fig. 12. 



46 STEAM HEATING FOR BUILDINGS. 

47. Horizontal multi- tubular boilers admit of very 
little modification ; an increase of diameter, with short 
shell and large tubes being best, for slow combustion, 
with a great distance between the grate and boiler, and 
no bridge-wall, other than enough to keep the fire on 
the grate. 

A chamber behind the bridge-wall is not of any par- 
ticular service, when the bridge-wall is low ; but mak- 
ing contracted throats, at the bridge-wall, or behind it, 
to make the heat " hug " the boiler, is a mistake. What 
is wanted in the furnace, and under the whole length of 
the boiler, is space sufficient for complete combustion. 
Below a certain size of cross section combustion is 
interfered with, and the oxygen which passes through 
the fire will not combine with the unconsumed carbon, 
which has been decomposed by the heat at the grate ; 
but with ample space this ignition will be continuous, 
until complete, with a sufficiency of oxygen, where the 
temperature is not below (800°) eight hundred degrees 
Fahr. 

For a high rate of combustion the boiler may be 
longer, with tubes of small diameter and with great 
space under the boiler. 

48. A contracted passage, or having only the area of 
the chimney at the bridge-wall, may impinge more heat 
on that particular part of the boiler, but it will not 
cause the evolution of more heat ; and the sum total 
remaining the same, it will do the same duty, whether 
absorbed by a small part of the boiler, to which it may 
do injury, or by the whole surface at a more general 
temperature. 

The extent of the sides of the furnace, when made 
of brick, may be used as an argument against a large 



BOILERS FOR HOUSE HEATING. 



47 



chamber ; but the loss through a brick wall is so little 
that it will not offset the benefit. 

Figs. 18, 19, and 20 show a horizontal multi-tubular 
boiler, as ordinarily set ; 18 being longitudinal section, 
19 half front and half cross section, and 20 floor plan. 

49. The different parts of boilers, and their settings, 
have technical 
names, applying 
to the correspond- 
ing parts of all 
boilers, as far as 
the construction 
will permit ; the 
shape, sometimes, 
modifying the 
name, and increas- 
ing or lessening 
the parts. As an 
example, a return- 
flue boiler, and a 
drop - return - flue 
boiler are shown 
(Figs. 9 and 10). 

The return-flue 
boiler can be used 
as a stationary or x 
marine boiler with 
or without a 
water-bottom ; the 
drop-return being 
constructed for stationary boilers, as it has no steam 
chimney, and the smoke connection is a sheet iron 
breeching. 




48 STEAM HEATING FOR BUILDINGS. 

A. Boiler-shell. 

B. Steam-dome. 

C. Boiler heads. 

C. Flue sheets. 

D. Tube. 

F. Flues. 

G. Back connection. 

H. Front " or smoke connection, 

I. Smoke 

J. Furnace, or fire-box. 
K. Ash-pit. 
L. Water-bottom. 
31. Steam chimney (marine). 
N. Smoke chimney (marine). 
0. Man-hole, to back connection. 
P. Bridge-wall. 
Q. Braces. 

B. Stay, or socket bolts. 
S. Grate bars. 
T. Coking, or dead-plates. 
U. Front-bearer. 
V. Back-bearer. 

W. Division, between front connection and fire-box. 
X. Boiler-fronts, cast iron. 
Y. Side walls. 
Z. Lugs. 

The division between furnaces, and the sides of fur- 
naces, are called "Legs" in fire-box boilers. 

The same letters apply to the corresponding parts of 
the horizontal boilers, Figs. 18 and 21. 




CHAPTER VI. 

FORMS OF BOILERS USED IN HEATING. 

The conditions required for heating boilers, which 
are of such proportions they may be fitted up to work 
automatically, are simplicity of construction, durability 
of parts, and ordinary economy in firing. 

50. A source of danger to the success of the young 
steam-fitter and to many inexperienced in steam-fitting 
— is their endeavor to construct ideal boilers, which 
usually prove to be failures. It is far better to use 
boilers proved successful by others, and improve their 
weak points, after your own experience with them. Suc- 
cess lies in that which will give hast trouble, and will 
not wear out rapidly — the burning of a few tons of 
coal more or less in a year, is not a proper test ; as the 
conditions of management, the size of the house, the 
amount of ventilation, the number of hours the ap- 
paratus is operated in the year, and last, though not 
least, the comfort and satisfaction — all must be taken 
into consideration to prove economy. 

51. Fig. 11 shows the simplest form of upright 
boiler, used for heating, excepting, perhaps, one with a 
flat crown sheet. The grate is drawn in at the bottom, 
by a slanting annular dead plate, as shown ; the center 

4 49 



50 



STEAM HEATING FOB BUILDINGS. 



Ziyff. 



part of the grate only has openings. The brick- work 
is very simple, and is built around the boiler, leaving 

about a three -inch 
space for a flue, and 
the smoke pipe is 
taken out at the bot- 
tom. It does not rate 
very high in point of 
economy of fuel ; but 
it is very easily kept 
clean, and lasts a long 
time. 

52. Fig. 12 shows 
an upright boiler 
(multi-tubular), which 
is drawn in at the fire- 
box, to the size for 
the grate. This dispenses with the annular dead plate, 
and makes a very permanent piece of work. This boiler 
is set to carry the heat, when it leaves the tubes down 
one side of the boiler, and up the other, passing under 
a septum of iron, or a division wall, which may be run 
very near the boiler, but so as not to press against it. 
"When the tubes of this boiler are not smaller than two 
and a half inches, or longer than three feet, and nothing 
but hard coal is used, it will require cleaning but once 
a year, provided there is no leak in the fire-box, or 
about the ends of the tubes.* To clean them,— remove 
the cover a', and use a steel wire tube brush. The 
cover a' is covered with sand, or fine ashes, on the top, 




* Much moisture causes the fine white ash which comes from hard 
coal to bake on the heating surfaces, and should be prevented. 



FORMS OF BOILERS USED IN HEATING. 



51 



and in the space c, around the top, to prevent radia- 
1 tion, or danger from fire. It will be noticed, this boiler 
is set on a cast iron plate, to give it stability. This 
plate is more satisfactorily made in two parts, and 
bolted together, which will prevent the heat of the fire 
from cracking it, after it is set. The grate is here 




shown, a little higher than it is usually set; but it 
would be well to keep it as high as the rivets. 

53. Fig. 13 shows the ordinary upright boiler, set for 
heating. It has a peculiar steam dome, as shown 
(patented), which prevents an excessive heat on top, 
and it is claimed slightly superheats the steam. It also 
has an ash-sifting grate, which saves much dust, in the 



52 



STEAM HEATING FOR BUILDINGS. 



manipulating of the ashes, and prevents the grate 
proper from burning out rapidly. 



!T?~^ — i . 




54. Figs. 14 and 15 show an upright multi-tubular 
drop tube boiler. Fig. 14 is a vertical section, on a 
center line, and Fig. 15, a half cross section, to show 
the walls and tubes. In Fig. 14, F P is the fire-pot, 
or dead plate ; F, the fire-box, or furnace ; G, the 
grate ; H, a bar set in the brickwork of the ash-pit, in 
such a way, it may be removed to put in a new grate, 
and into which the grate is pivoted, a certain distance 
below the edge of the fire-pot, to admit of shaking and 
cleaning from the bottom ; the amount of opening is 



FORMS OF BOILERS USED IN HEATING. 



53 



regulated by washers, on the pivot of the grate, to suit 
the size of coal used ; 0, the direct tubes ; a, the drop 




tubes ; J, the bottom plate ; K, the cover ; L, the direct 
chimney flue ; M, the bottom or drop chimney flue. 
In point of economy of. fuel, probably there is no 



54 STEAM BEATING FOB BUILDING S. 

Louse-heating boiler stands higher than this ; and in 
permanency, it is fully equal to any used ; besides, it is 
not difficult to clean. It will be seen that all the flues 
are internal, and if the gases of combustion cannot 
impart any heat, to the boiler, after cooling to a certain 
degree, they cannot abstract any from it ; as happens 
in external flues, when the gases cool to the tempera- 
ture of the steam, before reaching the chimney. 

It is also an excellent boiler where light power is 
desired, in which case the tubes may be of smaller 
diameter than would be used for heating, and longer, 
to suit a higher rate of combustion. 

When upright boilers are inclosed in brickwork, the 
outside is usually built square, to suit the door cast- 
ings, and for appearance ; but the inside is generally 
built round, three or four inches from the boiler, to 
make a flue or an air space, which will be the same 
distance from the boiler, at every part. If it is necessary 
to have a flue so constructed, with the outside still 
square, build two walls ; a round one and a square one ; 
but the inner one must not touch the outer, or the lat- 
ter will crack ; otherwise build the wall square inside 
and outside, as shown. 

When boilers are constructed for low-pressure heat- 
ing, have them built just the same as if they were 
intended to carry high steam, taking care the leg (the 
part formed by the side of the fire-box, and the shell 
marked N f in Fig. 14) is properly stayed with socket- 
bolts, or stay-bolts ; for boiler-makers often show a 
disposition to leave the legs unstayed, when they know 
the boiler is for very low pressure. 

Fig. 16 represents this boiler when set, and fully 
fitted with the necessary self-acting appurtenances. A, 



FORMS OF BOILERS USED IN HEATING. 



55 



is the main steam pipe, which must be run for no other 
purpose, but to distribute steam to the heaters ; B, 
the safety valve, with its auxiliary diaphragm ; (7, the 
draft-door regulator (the pipe carried up inside the 




brickwork ) ; D, the fire-door regulator, which is not 
absolutely necessary ; but it is well to have, in case 
anything should prevent the draft-door from closing; 
E, the automatic water regulator, whose connections 
should not be a branch, from any other pipe — nor 



56 STEAM HEATING FOB BUILDINGS. 

should they be branched for any purpose ; F, the main 
return pipe, which should have no valves in it, unless 
there are valves in the main steam pipe to correspond. 
But when there is but one boiler, it is generally better 
to dispense with valves in the mains at the boiler. G, 
the gauge cock, which for cleanliness may have a drip- 
pan under it, connected with the ash-pan; H, the 
blow-off cock, which in a heating apparatus should 
never be connected directly ivith the sewer or drain, but 
should be a lever handle cock, over a tunnel, as shown, 
to prevent the possibility of water passing out of the 
boiler, without the knowledge of the person in charge. 
The tunnel can be removed when not in use. I, the 
fire-door, on a good slant, so as to form a shute for the 
coal, and to close without a latch ; J, the draft-door, 
an attachment to the ash-door ; K, the ash-door, which 
is hinged to the frame L, and will open without inter- 
fering with the draft-door ; the chain and the bolt hav- 
ing nearly the same common axis; L, the ash-door 
frame, which is bolted to a skeleton frame, built into 
the brick work, and can be removed, to put in a new 
grate ; M 31, are hand holes, to clean the space at the 
bottom of the drop tubes ; N, a hand hole, to clean the 
upper tube sheet through, and through which a steam 
tube cleaner may be used, if desired. 

55. Fig. 17 represents a boiler, which came into 
public notice within A\e years, and has given good 
satisfaction.* 

It is a drop tube boiler, with a coal magazine, similar 
to the base burning stoves, and is entirely constructed 
of wrought iron, except the cast-iron magazine. When 
set, according to the manufacturer's instructions, every 

* It is the patent of Wm. B. Dunning, 



FORMS OF BOILERS USED IN HEATING. 



57 



part of the boiler is exposed as heating surface ; the 

heat passes between the magazine and the fire-box, and 

thence down the drop tubes, D, and up and around the 

k qsf 




shell. The magazine is made to pull out, and care 
should be taken when setting them, to have sufficient 
room overhead to accomplish this. 

It is claimed this boiler will run twelve hours, and 
keep steam without requiring attention during that 
time. They are manufactured for the trade, and parts 
of them likely to wear out (magazine, muzzle, grate, 
etc.,) are made in duplicate. 

56. Figs. 18, 19, and 20 show longitudinal section, 
half front elevation, and half-cross section ; and plan, 
of an ordinary horizontal boiler, set for heating or for 
power. 



58 



STEAM HEATING FOR BUILDINGS. 




This is the style of boiler most in use in the United 
States, when the building is of 
such proportions, an upright 
boiler is not deemed sufficient, 
as there is a prejudice against 
very large upright boilers. They 
are sometimes fitted with auto- 
matic appurtenances, but where 
two or more of them are in a 
building, automatic draft regu- 
lators are all that should be 
used ; and a careful engineer or 
fireman should do the rest.* 




1 


1 \ 










F1 rn 






X 


.- 7/ 


(( J3. )) ^ 


a 








UJ ud 






, 


yr 







* Apparatus fitted up automatically, and left for long periods, never 
should have more than one boiler. 



FORMS OF BOILERS USED IN HEATING. 



59 



When used for power where the water contains 
mud, they should be fit- 
ted with a mud pipe, as 
shown in Fig. 21, or if 
used for heating, when 
the water is not returned 
by some means ; but this 
is scarcely necessary in 
a gravity apparatus. 

Fig. 21 shows a hori- 
zontal boiler, where the 
front end of the shell is 
supported by resting in 
the cast iron front ; with 
the front connection 
formed, by what is known 
as breeching /this is 
sometimes made of light 
iron a*nd bolted on ; but 
it is better to form it by 
an extension of the boil- 
er shell, as shown. This 
dispenses with the divi- 
sion W y as shown in Fig. 
18. 

There seems to be a 
dislike to this front, for 
no better reason, than 
because it is not consid- 
ered ornamental. It is 
certainly a more sub- 
stantial front, and if set 
as shown, with deep dead plate, and two courses of fire- 





60 STEAM HEATING FOB BUILDINGS. 

brick lining, it will seldom require repairs ; but if the 
front bearer is bolted to the cast front, and the front, 
lined with a single course of fire-bricks, held in their 
place around the door, by a cast iron frame, the frame 
will burn off, the lining fall down, and the front become 
heated and cracked. With a straight front, a dead 
plate is always used, to carry the fire away from W, 
Fig. 18. The thickness of the wall necessary to form 
W, forms a lining for the front, which mast be kept in 
repair, or W will fall, and as W cannot be dispensed 
with in a boiler, set as in Fig. 18, the front is thus pre- 
served. If the dead plate is used, and made sufficiently 
deep, whether W is used or not, the front will last ! 

This front and setting also obviates the necessity for 
the projection, shown in Fig. 22, which is spoken of 
elsewhere. 

56h Plate 2 shows a horizontal multi-tubular boiler, 
similar to the boiler shown in Fig. 18, but with the im- 
proved cast-iron fire door arch, A; with the man-hole on 
the shell and sliding ash-pit doors. 

As there are more of these boilers used in New York, 
and other large cities, for heating and supplying power 
for elevators than any other type, it would be well to 
give them more than a passing notice. 

It is usual to make their shells of No. 1 charcoal 
hammered iron, — though many are now made of a certain 
grade of boiler steel. "When iron is used, shells up to 
36 inches should be made of J inch plate ; from 36 " to 
48"of T V thick plate, and from 48" to 60" of f thick 
plate ; with head sheets of f to T V and h respectively, con- 
structed of best flange iron. 

The domes of these boilers are usually made one-half 
the diameter of the shells, and about the same height ; 




HOMZONTAL-MULTI-TUBULAR-BOILER. 



FORMS OF BOILERS USED IN HEATING. 61 

but the limited height of cellars often reduces the 
height of the dome, and in some cases renders it neces- 
sary to dispense with them altogether. 

The height for the setting of a 48-inch shell, should 
not be less than 10 feet, and as much more as can be 
conveniently had. This will allow 2 feet from the pav- 
ing of the ash-pit to the grate, and 2 feet more from the 
grate to the boiler ; and though it is a little more than can 
be obtained with ordinary fronts now in use, it is not more 
than would be best to employ ; this is especially true in 
respect to the distance between the grate and the boiler. 

Low cellars are a detriment to a heating apparatus in 
another and very important respect — they bring the 
main steam pipe too near the water line of the boiler, 
and frequently cause the contractor to use a return trap 
on a job which otherwise could be made more perfect by 
a gravity apparatus. 

When the man-hole of a boiler is in the top of the 
dome, a hole in the shell underneath the dome, large 
enough to easily admit a man from the dome into the 
shell, is required. This is bad practice, as this large hole 
weakens the boiler materially : which fact engineers 
generally pay no attention to. The shell of a boiler 
underneath the dome should not be cut out ; but should 
be perforated with a number of small holes — say 2 inches 
in diameter, until their aggregate is three or four times 
that of the steam pipes. 

"When the man-hole is in the top of the boiler an extra 
heavy man-hole frame should be riveted to the shell ; its 
longest diameter being across the shell. 

The tubes in horizontal boilers give the best results 
when not " staggered " but placed in vertical rows, and 
should have at least one inch between the tubes at their 



62 STEAM HEATING FOR BUILDINGS. 

nearest parts, and should be not nearer the shell than 
3 inches. 

These boilers should be tested to 150 lbs. per square 
inch by hydraulic pressure. This is absolutely necessary 
to test the bracing and other parts, such as heads and 
man-hole frames. 

There is a prevalent idea that testing a boiler with 
cold water may injure it. If a boiler will not stand 
twice the ordinary pressure it is made to carry, without 
injury under a hydrostatic test, with water at 40 degrees 
Fahrenheit, it should not he put in. 



CHAPTEE VII. 

REMARKS ON BOILER SETTING. 

57. The best materials should be used in the set- 
tings of boilers, and less than a 12-inch wall should 
not be allowed even in the setting of the smallest class of 
horizontal boilers. Large boilers should have 12-inch 
walls additional to the thickness of the fire-brick lin- 
ing of the furnace, and 20, and 24-inch walls are not 
uncommon. 

It is not desirable to put a number of masons on 
boiler walls, and hurry them ; for neatness and deliber- 
ation are required with every brick, and makeshifts 
should never be allowed. 

58. On marshy, or sandy ground, it is well to excavate 
for the whole size of the apparatus, and put in a thick 
concrete foundation, which will keep the work sub- 
stantial, and helps to cut off moisture from the earth. 

59. It is generally assumed, that the greater expan- 
sion of the bricks, on the inside of the furnace, is the 
cause of boiler walls cracking ; and it is, to some ex- 
tent, true, but cracks from this cause are generally dis- 
tributed all over the walls, and are not so great that 
more than a few coats of whitewash are sufficient to fill 

them. 

63 



64 STEAM HEATING FOB BUILDINGS. 

The large fissures, which often appear in walls of 
boilers, are usually caused by an insufficient found- 
ation ; the walls resting on or against the boiler ; or by 
unequal or abrupt changes of thickness. 

The arch, over the back-connection of a boiler (see 
Fig. 18), should not be turned against the boiler, as is 
usually the case, but should be sprung from the side 
walls ; with a rod to form the cord of the arch, the rod 
to be just covered from the heat, in the back wall (see 
Fig. 18, at a'), and with the necessary flanges, or buck 
staves on its ends. 

If it is desirable to turn the arch from the back wall 
to the back head of the boiler (since some think this 
shape more desirable), use a heavy angle iron, to turn 
it against, and keep the angle iron half an inch from 
the boiler, taking care no mortar or bits of brick lodge 
between them (see Fig. 21, at a). 

"When the lugs of a boiler are firmly built into the 
brickwork, without iron plates in the wall, for the lugs 
to " give and take " on, the walls will crack, because the 
iron of the boiler contracts and expands more than the 
wall does. 

The arch, turned over a boiler, should not touch it, 
but there should be one or two inches of space between 
them ; the arch should spring from the side walls, and 
be self-supporting, and not turned on the boiler. 

A good way to build these arches, is to lay inch strips 
of wood lengthwise on the boiler, and draw them out, 
as the work progresses. 

When boilers are not arched over but the side walls 
are run straight up, and the space, over the boiler, filled 
with sand, the walls are very apt to crack and shove 
them out of plumb. Every time the boiler cools, sand 



REMARKS ON BOILER SETTING. 65 

will pass down between the boiler and the wall, and the 
whole mass of sand will settle down; when the boiler 
becomes heated again, and expands, the sand will not 
go up again, hence the wall is shoved out. This often 
occurs, and it is blamed directly to the action of the heat 
as something unavoidable. 

When boilers are set on sandy ground, the foundation 
should be deep, and good, or the heat of the furnace 
will drive out the moisture from the sand, and leave it 
a quick-sand, which will allow the walls to settle. 

An air space within a boiler wall is not of any service, 
the same thickness of brick would prove more service- 
able and will not weaken the wall.* 

60. The fire-brick, in a furnace, should have the 
smallest possible quantity of fire-clay between them, 
barely sufficient to level the work ; and it should be laid 
with a couple of courses of headers at the top, so the 
side linings could be removed, without effecting the 
stability of the wall. The other courses should not have 
headers, as the breaking out of a row of headers will 
injure the wall. 

61. The division ( TV, Fig. 18) between the furnace and 
the front-connection, is another source of annoyance ; 
when constructed of iron, it burns out rapidly, and 
when made of fire-brick, in the shape of an arch, it falls 
out ; or may often be broken in using the fire tools. 

Hollow castings, with air and water circulations in 
them, have been tried ; but do not last. The shell of 
the boiler is sometimes allowed to project, and cover 

* I do not wish to convey the idea that a space in the walls of a 
building is not valuable ; since it interrupts the passage of moisture, 
the evaporation of which, from the walls, will require more heat than 
would be lost otherwise. 
5 



QQ STEAM HEATING FOB BUILDINGS. 

the space ; but as it has heat on both sides of it, it 
buckles and burns out, in a year or so. 

Sometimes the shell is extended with a water space, 
formed on it by a projection of the head sheet and 
shell, which forms a permanent fixture ; and, if the part 
is well studded with stay-bolts, there can be no objection 
to it ; but care must be taken, when great pressure of 
steam is to be used, as this " shovel nose " will form 
the weakest part of the boiler (see Fig. 22). 




If an iron arch is used underneath a brick arch to 
support it, and keep it from being knocked out, it will 
last longer ; but the inner edge of the casting will bulge 
down, and get out of shape, long before the iron will be 
burned away, which suggested to the writer, that if the 
cast arch (which should spring from the dead plate, and 
form the doorway to the furnace) flared inward, and 
was cut into, for about one third its depth, making 
large and course prongs (about 2" wide, with one inch 
of a slot), to support and guard the bricks, it would 
stand for a long time. This method has been used for 
3 \ years, and the prongs have not bent down, while they 
burn off very slowly from their points, not being short- 
ened even £ inch ; but only rounded on their ends. 



REMARKS ON BOILER SETTING. 67 

62. A deep dead-plate saves the front linings, as it 
keeps a body of comparatively dead coals, between the 
front and the fire. 

63. Bridge walls are often built straight across, but 
an inverted arch is better ; not on account of combus- 
tion, but in an arch, the bricks are keyed in, and are not 
as likely to be poked out by the fire tools. 

64 Deep ash-pits are the best, and a second or ash- 
grate, will help preserve the grate-proper; as there is 
less reflection of heat from it, than there would be 
from a hard brick bottom. 

65. Lugs on boilers. 

The brackets riveted to the sides of boilers to support 
them in the brickwork, are commonly called " lugs," and 
many engineers, in the construction of what they con- 
sider long boilers, put three on a side, fearing the 
weight will be too great for two only. This is evidently a 
mistake, and frustrates the object for which the third is 
put on. The settling of the brickwork at one end, will 
then throw the whole weight of the boiler on the middle 
pair, and even if the walls should not settle, the heating 
of the under side of the boiler more rapidly than the 
top (which may often take place, for instance, upon 
starting a fire, before steam is up), will, in a measure, 
force up the ends, leaving the whole weight on the mid- 
dle lugs. 

Four lugs properly put on, are found to be the best 
number. 

Lugs are sometimes left off, until a boiler is in the 
basement, for the purpose of getting it through door- 
ways. This is not wise, as the rivets should be driven 
on the inside of the shell, before the tubes are put in 
Putting them on with tap bolts is not good, as two or 



68 STEAM HEATING FOR BUILDINGS. 

three bolts may have to carry the whole end of the boiler ; 
and should they leak, the side wall would have to be 
torn down. 

A good plan when the lugs must be left off, is to have 
a shoe riveted to the boiler at the proper time, into 
which they will slip, similarly to a stove leg ; which 
must be sufficiently strong for the work. 



CHAPTEE Yin. 

PROPORTIONS OP THE HEATING SURFACES OF BOILERS 
TO THE RADIATING SURFACES OF BUILDINGS. 

66. There is no simple relation, between the heating 
surfaces of boilers, and the radiating surfaces of the build- 
ings they have to supply the steam to, for the following 
considerations apply to every type of boiler: the 
method of setting, what the grate surface is, the charac- 
ter of the work they are designed for, and whether the 
air is simply to be maintained at a certain temperature, 
as in direct radiation, or whether every cubic foot of 
air which comes in contact with the radiator must be 
warmed from the outside temperature, as in indirect 
radiation, or whether the apparatus is direct-indirect 
or composite, all these would have to be considered, and 
the results would then be only approximate ; for even 
then, neglect of cleaning, a certain amount of neglect of 
management, and the state of the fire — whether on the 
first hour of the new fire, or the last hour of the dirty 
fire, for the time they are to run, must enter into this 
calculation. 

If the effect of the cooling, produced by loss, through 
the glass and walls of a building can be estimated, and 
added to the amount of heat lost in warming the air ad- 

69 



70 STEAM HEATING FOB BUILDINGS. 

mitted for ventilation, a close estimate can be made of 
the smallest grate, which would burn fuel enough to 
evaporate the amount of water in a boiler sufficiently 
large ; but these points the constructor must never loose 
sight of in estimating for an automatically fitted boiler, 
— namely, that it is the amount of opening of the draft 
door, which regulates the fuel burned ; next, the fuel 
burned regulates the water evaporated ; and, finally, the 
water evaporated regulates the heat — both the heat of 
the room (by having a sufficiently large heater) and the 
heat (or pressure) necessary to move the diaphragm, 
which regulates the draft, so that really what is re- 
quired are certain limits, ivithin ivhich he knoivs he is safe, 
and to exceed which would be an unnecessary expense. 

Boilers for very large buildings, which have an en- 
gineer in charge, may be figured pretty closely ; as he is 
supposed to be constantly at his post, and to clean his 
boiler fires regularly, and to fire often, and in small 
quantities ; keeping his fire door open the shortest time 
possible, and further, to clean the tubes or flues when- 
ever required. But this is not the case in house boilers, 
they must run for long periods without cleaning or in- 
terruption, and be adequate to every contingency of 
change within their limit of time to keep steam. 

It has been found by experiment in a general way, 
and from practice, that for ordinary buildings, with 
average window surface, and for the greatest range of 
temperature in our northern states, when nothing but 
direct radiation with no ventilation is used, one square 
foot of boiler to every ten square feet of the radiating 
surface will ansiver ; assuming the radiating surface is 
ample. 

For indirect radiation, if the heating or radiating sur- 



PROPORTIONS OF SURFACES. 71 

face of the coils are figured double, what they would be for 
direct radiation without ventilation, the same proportion 
of boiler to coil will suffice ; but, if instead of doubling, 
the same surface be used or a slight increase as i or &, 
and the building be kept warm by moving the air faster, 
through a small coil — we must double the surface of the 
boiler — that is, allow one square foot of boiler surface 
to 5 square feet of coil surface, the surface is to be 
figured as for direct radiation ; bearing in mind, a boiler 
is proportioned to the cooling which goes on — heating, 
ventilating, etc., and not to the coil surface, unless the 
coil surface is ample for the conditions of temperature, 
etc. 

When air is forced (as with a fan), more heat can be 
taken from a coil in the same time, than when the air 
moves naturally, from a difference in temperature ; but 
as the heat necessary for the building remains the same, 
the boiler must be proportioned to the building, and 
when the proper coil surface has been found — sufficient 
to maintain the heat, for the range in temperature inci- 
dental to the climate, and local conditions, it establishes 
the simplest data from which to calculate the boiler. 

For direct-indirect radiation, proportion the boiler 1} 
times greater than it would be for direct radiation. 

These estimates are for boilers with ordinary high 
combustion, such as horizontal boilers which are kept 
clean without interruption ; but for house boilers 
(wrought iron shell) with slower combustion, an ad- 
dition of from J to £ may be used, and in water tube 
boilers (pipe boilers) J to 4- may be added, in the judg- 
ment of the fitter. 

The manufacturers of the boiler, shown in Fig. 11, 
make 3 sizes, of 45, 60, and 75 square feet of heating 



72 



STEAM HEATING FOR BUILDINGS. 



surface, and say they will furnish steam for 300, 500, and 
700 square feet of direct radiation coils. 

The manufacturer of the boiler, shown in Fig. 13,* 
publishes a list of 24 sizes of boilers, from 54 square 
feet of surface to 400 square feet, in which he gives the 
maximum and minimum number of cubic feet of air in 
ordinary buildings, each boiler will carry radiation for ; 
his apparatus being all indirect 

The following is a condensed table of this list : 







Maximum and Minimum of 


No. of Boiler. 


Feet of Surface of 


Cubic Feet of Air in 




Boiler. 


Building. 


1 


54 


18 to 25 thousand. 


6 


107 


40 " 54 


9 


151 


55 " 75 


12 


202 


72 " 100 " 


18 


302 


116 " 152 


24 


403 


164 "215 " 



There is no doubt this list is ample when upright 
multi-tubular boilers are used, or any kind of shell 
boilers, with simple parts. 

It will be seen that by figuring the radiating surface 
of a building, by the old rule of allowing ten square 
feet of pipe or plate surface to each one thousand 
cubic feet of air (minimum) for direct radiation alone, 
and then doubling it, as mentioned for indirect above — 
the result agrees very nearly with the maximum num- 
ber of cubic feet in the list ; the difference between 
maximum and minimum forming a factor for safety, 
when the difference in construction of buildings and in 
neglect of management is considered. 

* Major Light. A steam-heating engineer of many years' experience. 



PBOPORTIONS OF SURFACES. 



73 



Morris, Tasker and Co. give a list which rates are 
nearly the same, the variation for circumstances being 
greater. It is as follows : 



Feet of Surface of Boiler. 



115 
125 
133 

148 



Contents of the Building in Cubic Feet. 



18 to 30 thousand. 
26 " 43 
37 " 62 
55 " 92 



In the Nason Manufacturing Company's circular is to 
be found the following list — in which the grate to the 
heating surface of the boiler is about as 1 to 27, and the 
heating surface of the boiler to the radiating surface of 
the building 1 to 6 \. 



Square feet of Grate 
Surface 

Square feet of Boiler 
Surface exposed to 
the fire 

Square feet of Radiat- 
ing Surface which 
it will heat 1350 



2 


2i 


3 


3| 


4 


u 


5 


6 


55 


65 


78 


83 


105 


116 


131 


158 


350 


440 


525 


600 


700 


775 


900 


1050 



7 

182 

1225 



CHAPTEE IX. 

GRATES AND CHIMNEYS. 

67. For a house heating apparatus, the grate and 
fire-pot should be so constructed, that as the fire 
burns, the body of fuel will move together, centrally as 
well as downwards, and thus keep a compact body of 
ignited coal for a long time on the grate. When a 
grate is broad, with a thin fire on it, the fire burns out 
at certain parts of the grate faster than at others, and 
a fireman has to build his fire accordingly, giving it 
constant attention to keep up steam and not waste 
coal ; but in a private house, all parts of the appar- 
atus, including the grate and fire-box, must be con- 
structed so that the fire can be left unattended for a 
comparatively long time ; and engineers unacquainted 
with this class of work, will be surprised at what has 
been done in this respect ; six hours' duration being 
common for a fire to keep steam, arid make a better 
showing, for the same weight of coal per radiating 
surface, than large boilers with flat rectangular grates, 
fired regularly and often, with a high rate of combus- 
tion. 

"When a grate is surrounded with a fire-pot, or when 

the fire-box is drawn in, to any angle not greater than 

74 



GRATES AND CHIMNEYS. 75 

30° from the perpendicular, the coal as it burns will 
press to the center and slip cloven, keeping a deep fire 
in a good condition longest. This is necessary in an 
apparatus constructed to run all night without atten- 
tion, unless it is constructed with a magazine, as in a 
base burning stove. It can be understood by reference 
to Figs. 12 and 14 of upright boilers.* 

68. Grates should be proportioned to the heating 
surface in the building, radiating surface, and the water 
to be evaporated, assuming the boiler to be sufficiently 
large. 

69. The chimney must be capable of passing suffi- 
cient air, for the greatest consumption of fuel likely to 
be used. Less air will not do ! More than is needed 
does no harm ; for it is within the power of the opera- 
tor, or the automatic draft regulator, to diminish it. 

Again, the openings in the grate must be large enough 
to pass sufficient air, when the fire is packed with ashes, 
in the last hour it is supposed to run, ivithout attendance* 
Smaller ones will not answer, and much larger are 
unnecessary ; although there is considerable scope in 
this latter respect, as it is the constant opening or 
closing of the draft-door, which really regulates the 
proper quantity of air supplied. As theoretical values 
and sizes in grates and chimneys are of very little use 
to the artizan, — the formula being all founded on con- 
ditions, which give them only relative values and estab- 



* The writer thinks this same principle has been applied to locomo- 
tive boilers in England. The drawing in of the lower part of the fire- 
box, at a steep angle, all round the grate, allows the fire to shake down 
and together, by the motion passing over the rails, while the wedge 
shape keeps the fuel at the same density for the whole time, between 
the firings. 



76 STEAM HEATING FOR BUILDINGS. 

lish laws, that even in the hands of an educated 
engineer, leave too much to be assumed — the writer 
believes it would be better to tell from practical results 
and experience what has been found sufficient, and what 
lias not, rather than copy some formula from a text 
book. 

70. The following four examples have been selected, 
from actual experience, as they represent, very nearly, 
a minimum. 

1st. A chimney, 130 ft. high (built in the walls of a 
building), 16 " by 32 " (512 square inches), with two 
horizontal multi-tubular boilers attached; each grate 
17| square feet (35 in all), burning 9J lbs. of coal per 
hour for each square foot of grate, and evaporating 
11 lbs. of water from the temperature of the return. 
The grates having a whole area of 5,040 square inches 
and 2,016 square inches of openings, compared with 512 
square inches of cross section, in chimney 130 ft. high, 
giving a rate of combustion of 9J lbs. coal per square 
foot of grate, 23 f lbs. per square foot of openings in 
grate, and 93 T 6 F lbs. per square foot of cross section in 
chimney, per hour ; which, by allowing 200 cubic feet of 
air, at the temperature of 100° Fahr., necessary for the 
combustion of one pound of anthracite coal, which will 
be, at the least, increased to 300 cubic feet, by expan- 
sion, by passing through the fire, will give a velocity of 
the gases in the chimney of very nearly 8 ft. per second, 
and should the gases be increased to double their bulk, 
by discharging them at a higher terminal, the velocity 
will be very nearly 10-5 ft. per second ; giving about 
one third the theoretical velocity. 

The above chimney proved just sufficient for the 
work ; but if the engineer who proportioned the boilers, 



GRATES AND CHIMNEYS. 77 

and set them, had the construction of the chimney also, 
he would have made it more equilateral and increased 
the cross section one half. 

In the same building there were three such boilers 
(reserve), connected to the very same size and height of 
a chimney, but when the three were run together, there 
was so little gained, if any, the fireman preferred to run 
but two. 

2d example was, where a horizontal boiler with 4x4 
= 16 ft. grate was attached to a 16-inch circular, cast 
iron chimney 75 ft. high, built within a ventilating flue. 
The whole area of the grate was 2,304 square inches, 
and the spaces 920 square inches, the cross section of 
chimney being 201 square inches, and rate of com- 
bustion 6 lbs. per hour per square foot of grate 
(Pittsburgh coal), automatically regulated at tha chim- 
ney. 

3d example was a chimney 80 ft. high, 20 by 20 
inches (400 sq. inches), two boilers, each 4 by 4 ft. 
grates, in all 4,608 sq. inches of grates, with 1.840 sq. 
inches of space, burning 4,000 lbs. of coal in 14 hours, 
nearly 9 lbs. per hour per sq. foot of grate, although it 
was thought desirable to burn more. Still it will be 
seen it burned 100 14 lbs. of coal for each sq. foot of 
cross section of chimney per hour, which was better 
than the chimney 130 ft. high, with the oblong cross 
section. The velocity of the gases, allowing 400 cubic 
feet for each pound of coal after combustion, was 11-1 
ft. per second, which would tend to prove that the 
square chimney, 80 ft. high, would pass more gas per 
sq. foot of cross section than the flat chimney 130 ft. 
high, other things being equal. 

4th example was a horizontal boiler with 5 x 5 = 25 



78 



STEAM HEATING FOR BUILDINGS. 



sq. ft. of grate, one third openings, the chimney 16 x 16 
inches (256 sq. inches), and 60 ft. of its length was in 
the walls of building, with 15 ft. of iron stack, 18 " in 
diameter, 254-5 sq. inches on top of it; the latter was 
put on with a view to improve the draft, but all proved 
insufficient for the work to be done. 

A new chimney, 18 by 24 inches, was built 75 ft. 
high, all of brick, which proved a success, and burned 
273 lbs. of coal in an hour, giving a chimney velocity of 
10 ft. per second, and burning 10 9 lbs. of coal per sq. 
foot of grate (the new grate had f ths openings), and 
burning 90 1 lbs. coal per sq. foot of cross section of 
chimney per hour. 

71. The following table is a digest of the above, 
showing the relative values : 



d 

.2 
1 

M 


© 

o 

.5 
>> 

© 



a 
s 

o 

4-1 

o 

'© 
W 

130 
75 
80 

60 + 
15 

75 




>> 

© 

Sri 

I! 

<D CO 
CO 
00 
O 

512 
201 
400 

256 

432 


>> 

a> 


| 

u S 

<t-C ^" 

O a> 

§1 
"43 a" 
o so 
© 
co 

CO 

oo 
O 
Sh 

o 

3.56 
1.4 

2.78 


© 

1 

o 

o 
© 

© 

a 1 
cc 

37.5 
16.0 
32.0 


.s 

c 

*2 
© 
ft 

o© 

I 

3 


© 
1 

Em 
O 
co 

© 

© 

.s 

© 

p 

a 1 

02 


.2 

to 
tJC 

.2 
'2 

© 

ft 
o 

«H © 

°S 

4> 60 
XI 
o 
P 

e 

03 

a* 
02 


i.i 

© 3 

© P 

I 1 


C7 1 

© <- 

*.§ 

©— ■ 

SS 

g & 

p © 

© g 

8° 
*! 

■Q 

•-3 


© 
ft&fi 

© 

S £o 

B o* 

<*-> s - 1 

oo « 
©+J ft 

r- O © 

* O +5 

0«H. g 

O <=3 % C 
to o* 

X CO 


SI 

fto 

-do 
© c 

lis 

U CO ft 

o £ © 

S © c 
o° 

3- 


>•> 

©tH 

So-g 
"S © 

£?v © 
111 


© 
© 

© 
© 

8 

o 

i— i 


Dimensions and shape of chim- 
neys in inches. 


l. 


14.0 
6. 30 

12.78 


5,040 
2,304 
4,608 


2,016 


11 


9.5 
6.0 
9.0 


23.75 


93.6 


8.0 


10.5 16x32 


2. 


920 








.. |l6"diam. 


3. 


1,840 


22.54 


100.14 




11.120x20 


Old 
4. 


1.78 
3.0 


25.0 
25.0 


83.3 
10.0 


3,420 


1,324 












16x16 
18"diam. 


New 


3,420 


1,440 




10.9 


27.25 


90.1 




10.0 18x24 

1 



72. From the above table, the following conclusions 



ORATES AND CHIMNEYS. 79 

may be drawn — viz., that for rectangular chimneys, 
between 50 and 100 ft. high, with not less than 16 
inches on the shortest side, one square foot of cross 
section of chimney, to each 75 lbs. of coal to be burned 
per hour, would be safe ; and that for rectangular chim- 
neys, 30 to 50 ft. high, with not less than 16 inches on 
the side, one square foot of cross section, to 50 lbs. of 
coal burned per hour will be sufficient. 

An 8 x 12 inch chimney is the smallest that should 
be built in a house for a heating apparatus ; not be- 
cause it will require that size chimney for the combus- 
tion of the coal, but to give a practical magnitude for 
roughness and want of cleaning, etc., and no other pipe 
should be taken into it. 

For apparatus, such as are put into large mansions, 
which burn 40 to 50 tons of coal in 180 days, a 12 x 16 
inch flue is little enough for the above reasons. 

Care in building a chimney is necessary, a smoothly 
plastered chimney giving a better draft and keeping 
clean longer than any other. Offsets in chimneys 
should be avoided, and parallel insides are best. 

It will also be noticed that the low pressure auto- 
matically regulated boiler, had one square foot of grate 
to each six po,unds of coal burned per hour, and that 
the high pressures, with quick combustion, had one 
square foot of grate to each ten pounds of coal, or even 
a little more. The latter agreeing very nearly with 
arbitrary rules laid down in hand-books. 

Thus for large boilers, fired regularly with ordinary 
good draft, one square foot of average grate (nearly £ 
openings) to each 10 pounds of coal, forms an average ; 
but for conditions such as are found in private houses, 
or where the apparatus is governed automatically, and 



80 



STEAM HEATING FOR BUILDINGS. 



expected to run comparatively dirty (with an accumu- 
lation of ashes on the grate, as happens with thick fires 
attended to at long intervals), one square foot to each 
five pounds of coal burned in the hour is not too 
much, and may be used with safety. * 

The following table gives the number of inches in 
diameter for circular grates, from one square foot to 
six, inclusive ; advancing by J of a square foot. 



Diameter of Round Grates in Inches. 


Square Feet of Surface in Grate. 


13£ inches. 


1 feet. 


15 


<« 


li " 


16| 


Cl 


1* " 


18 


(t 


n « 


19 h 


it 


2 " 


20£ 


a 


2i « 


211 


a 


21 « 


22* 


it 


2} " 


231 


ti 


3 " 


24^ 


tt 


31- « 


251 


a 


31 " 


261 


n 


3| " 


27 h 


tt 


4 " 


28 


a 


4* " 


28| 


a 


41 « 


291 


it 


4| " 


m 


it 


5 " 


31 


a 


5j » 


31f 


" 


5A " 


321 


a 


r oi " 


33> 


a 


G " 



73. Why grates break ? 

Round grates made of concentric rings, and straight 



* It is supposed the grate is half bar, and half opening. If the open- 
ings are less than half, increase the grate in diameter until there is a 
rate of one square foot of opening to each 10 lb. of coal burned in the 
hour. 



GRATES AND CHIMNEYS. 



81 



radial arms, always break and fall to pieces, never 
wearing out in the ordinary way. There is usually the 
same result with parallel bars, confined with a ring, 



JVjM 



Fie/. 24. 




and they are the two forms most likely to be made by 
any one who is required to get up patterns and has not 
had experience in the matter ; since the pattern for the 
straight-barred grate is so much easier to make. The 
6 



82 STEAM HEATING FOB BUILDINGS. 

reason of breaking is, because the thrust of the straight 
parts of the grate is not compensated for when expan- 
sion takes place, and a rupturing of the rings is the 
result. 

In this matter, it would be well for the engineer to 
take pattern from the stove manufacturer, and follow 
him in this respect. No straight bars are here used in 
circular grates, as a rule ; or, if he has to use straight 
bars, they are short and unconfined at one end, radiat- 
ing in or out. 

The same principle applies to all grates ; the old- 
fashioned three-barred grate fails by reason of the ends 
dropping off, and that, when it is least expected, caused 
by the unequal thrust of the bars against their ends, and 
quietly cracking them in the angles, where they are the 
weakest. Figs. 23 and 24 show grates that will crack ; 
Figs. 25 and 26 show grates which will not crack, if 
very sharp corner angles are avoided by rounding 
them a little. 



CHAPTEE X. 

SAFETY VALVES. 

74. Every boiler, for the generation of steam, for 
power or heating, must have a safety valve. 

A perfect safety valve is a desideratum, for with a 
valve of sufficient area that would respond to the 
desired pressure of steam, an explosion from over- 
pressure would be an impossibility. 

Many boilers burst when working at their ordinary 
pressure y and mysterious unavoidable causes are often 
assigned as the reason ; but there is only one reason — 
insufficient strength; either from a defect of construc- 
tion, or by deterioration of the material, or neglect ; 
and in a case of this kind no safety valve can respond, 
the valve being set for a higher pressure than that at 
which the boiler explodes.* 

75. The office of the safety valve, being to relieve the 
boiler of pressure, above its ordinary working pressure, 
it must be large enough to let the greatest quantity of 
steam, ever likely to be made, escape freely. 

* The writer has entered boilers where pins were out of braces, and 
braces broken : and one case where the mud deposit in a horizontal 
boiler covered four rows of tubes at the back end, cracking and bulging 
the shell ; the bank of mud, apparently, holding the boiler together. 

83 



84 STEAM HEATING FOR BUILDINGS. 

In proportioning safety valves for small boilers, and 
in fact for most boilers, the size is simply guessed at; the 
engineer or fitter puts on a certain size valve, because 
he is in the habit of doing so, or because some former 
employer did it ; having in mind the while, an idea, that 
if a certain sized pipe, carried all the steam the boiler 
could make to the engine, a safety valve very much 
smaller in area would answer, since it escaped into the 
atmosphere only — not knowing that a two-inch safety 
valve blowing off at 60 lbs., had an opening so small 
that if it was round he could not put his pencil through it. 

76. "When a valve begins to blow off, the pressure 
underneath the disk decreases, out of all conceptional 
proportions ; the decrease not being due to a diminution 
of the pressure in the boiler (as the steam may actually 
be increasing), but to the draft caused by the escape, 
the laws of which are imperfectly understood, but the 
results being conclusively proven, by Prof. Throw- 
bridge and others ; the proportional difference being 
greater for greater pressures. 

77. Professor Burg, of Yienna, found by measurements, 
made by actual experiments, with an apparatus con- 
structed for the purpose, that a valve of 4 inches di- 
ameter, raised from its seat, when blowing off, according 
to the t ico first columns of the following table. The last 
two columns are calculated, that the fitter may form an 
actual conception of the openings, by comparing them 
to something he is perfectly acquainted with. 

The first column is, lbs. per square inch ; 2nd, actual 
lift in fractions of an inch ; 3d, actual size of openings 
in decimals of a square inch, when the bevel of the 
valve seat is 45 degrees ; and the 4th, the internal nomi- 
nal size of gas pipe, nearest the actual opening. 



SAFETY VALVES. 
TABLE No. 2. 



85 





1. 


2. 


3. 


4. 




Prets. 


Lift. 


Area. 


Pipe. 




12 


.1. 

36 


.25 


JL 
2 




20 


-1- 

48 


.187 


3. 

8 




85 


1 

6 4 


.106 






45 


& 


.137 






50 


^ 


.1043 


* 




90 


_1_ 
1 1> 8 


.0534 


i 



78. The following graphic illustration has been 
made to show at a glance the size of the openings : 




ACTUAL SIZE. 



the large rim, inclosing the area of a 4-inch disk (12.56 
square inches), and the smaller ones, the areas of the 
openings at the different pressures. 



86 



STEAM HEATING FOR BUILDINGS. 



It can be seen from the foregoing, that an increase of 
pressure lessens the size of the opening ; nor do the in- 
creased pressure, and flow of the steam, compensate for 
the decrease in the size of the opening, and what is re- 
quired is a valve of very great diameter, or one that will 
open its full area. In this latter respect the steam-heater 
has done much, as will be shown hereafter. 

79. There^are many formulae for calculating the size 
of safety valves, all based on the size of the disk ; and, 
though arbitrary, may be useful, as they give sizes, 
about four times, the area of ordinary practice. 

Fairbairn allows 29 square inches for a 50 horse- 
power boiler. 

Rankine says : " Divide the number of lbs. of water 
which enters the boiler in an hour (to supply the loss 
by evaporation), by 150, and the product is the area of 
the valve in inches." 

Bourne says : " Multiply the area of the piston in 
inches by its velocity in feet per minute, and divide by 
300 times the pressure of the steam, and the product is 
the area of the valve in inches." 

According to the relative volume of steam, at half its 
theoretical velocity when flowing into the air, two square 
inches of actual opening of valve should be ample for 
the number of cubic feet of water evaporated per min- 
ute, at the different pressures given in the following 
table : 



Pressure in boiler above 
atmosphere. 


Cubic feet water evapor- 
ated per minute. 


Actual size of opening in 
valve. 


25 

50 

100 


1.0 
1.9 

3.2 


2 square inches. 

2 " 

2 " " 



SAFETY VALVES. 



87 



By a study of the above, it will be seen that if a 
boiler is of such construction, that 25 lbs. of steam is the 
maximum, it will require a larger valve for the same 
amount of water evaporated than a high pressure boiler, 
and that indiscriminate rules are not to be used. 

80. There has been much effort to obtain a safety 
valve which will give a large opening, and in some in- 
stances, valves thus made, have proved practically a 
success, though not in general use, since the necessity 
for them is not recognized by the public, who content 
themselves with a danger signal, where the noise it 
makes when blowing off, is all that can entitle it to the 
name of safety valve. 

Fig. 27 shows a common safety valve, with an auxili- 
ary attachment, which is 
capable of pulling the 
valve open to its full ex- 
tent. A is an ordinary 
safety valve, put on in 
the regular way ; B, a 
common low - pressure 
diaphragm or regulator 
(see draft regulator for 
construction), attached 
to the end of the lever, 
and suitably fastened to 
the boiler ; with the 
pipe connection C, to 
the under side of the diaphragm, and taken from the 
water space of the boiler, for two reasons, — namely, that 
the water in the pipe may be cold, so as not to affect 
the rubber of the diaphragm, and the water, being 
steady and solid, prevents vibrations, and gives the 




88 



STB AM H EATING FOR BUILDINGS. 




initial pressure unaffected. Fig. 28 shows the same in 

a position to blow off, the pressure under the rubber 

overcoming the weight. 

When steam begins to escape, it cannot affect the 

diaphragm until the press- 
ure in the boiler falls, when 
the diaphragm subsides. 

This same principle can 
be applied to high pressure 
safety valves, by using a 
diaphragm, especially con- 
structed, as in high pressure 
damper regulators. 
The escape pipe {D, Fig. 27) is sometimes carried 

down, and under the grate, by steam-fitters, that the 

escaping steam may damp the fire, 

and check it ; by interfering with 

combustion : a point worthy of con- 
sideration by all engineers. 

Another arrangement for very low 

pressure is a water column, con- 
nected as in Fig. 29. A connection, 

A, is taken from the steam space, 

and carried down and up, forming an 

inverted siphon filled with water. 
When the pressure in the boiler 

exceeds the weight of the column 

of water in the pipe, it blows it out, 

letting the steam escape, which will 

blow until the steam is all gone, or 

the pipe again filled with water. 

A modification of this principle has been constructed, 

by which steam can be carried to about 12 lbs. per square 




SAFETY VALVES. 



89 



Fig 30 




inch, in buildings of ordinary height. A cylinder of 
any suitable construction is connected to the boiler, as 
shown in Fig. 30, and filled with water ; the pressure 
of the steam through the pipe (a) 
on the surface of the water in the 
cylinder, presses it up in the pipe 
(b) ; but when the pressure is great 
enough to send the w T ater over 
into the pipe (c), the steam es- 
capes at (d). This arrangement, 
like the one before, will not stop 
blowing without manipulation ; it 
being necessary to close the valve 
(e) and open the valve (/), to let 
the water again into the cylinder. 

A boiler with this arrangement 
on it, should also have a common 
safety valve set at a lower press- 
ure, to give warning, for should 
this start to blow off, and be neg- 
lected, it will waste water and 
steam from the boiler. The pipe 
(a) may be long, so as to have the 
cylinder a considerable distance from the boiler : in one 
case where it was set against it, the heat evaporated the 
water from the cylinder. 

A boiler with a water column on it, as described, 
should have a vacuum valve also, to prevent the water 
from being drawn into the boiler, when steam goes 
down. 

Another arrangement, which has been tried with 
some success, is an ordinary safety valve of large size, 
with a pipe (a) carried from the under side of the disk, 



90 



STEAM HEATING FOR BUILDINGS. 



down into the water in the boiler, as shown in Fig. 31 ; 
the orifice of the valve forming an annular space around 
the pipe. 

The philosophy of this valve is — that the pipe being 




carried down into the water, represents a certain area 
of the disk, which would be of scarcely any value when 
blowing off, but by being in the water, the pressure un- 
derneath it is not relieved. 



CHAPTER XL 

DRAFT REGULATORS. 

81. When the steam-heater wishes to govern any- 
thing automatically, his first thought is, whether a 
diaphragm answers, and if he can regulate what he 
wants with a rubber diaphragm, he will never resort to 
a moveable piston : knowing the diaphragm will work 
until it wears out, without getting out of order, and 
that a piston must be kept in the nicest of order to be 
depended on, since it is affected by corrosion and dust, 
while the diaphragm, being simple and cheap in con- 
struction, and having no delicate parts, will respond to 
the smallest difference of pressure, and will run for 
many years, when constructed and put on by one who 
understands it. 

The steam-fitter uses it to regulate the ash-pit door, 
for the admission of the proper quantity of air to the 
fire, to govern the steam pressure ; to open the fire- 
door, to admit cold air through the furnace, in case the 
draft-door is neglected, by leaving a clinker or lump of 
coal underneath the edge ; to open the safety valve, 
and sometimes to open a "break draft," an opening in 
the chimney. He also uses it for regulating the air 
supply to indirect radiators ; to govern the pressure of 

91 



92 



STEAM HEATING FOR BUILDINGS. 



steam, when expanding from high to low pressures, in 
different systems, and to regulate water pressures with. 
82. Fig. 32 shows a regulator of ordinary construc- 
tion, with a bowl at the top and bottom of the dia- 
phragm, in which A is the bottom bowl, to which the 
support and pipe are attached ; B, the upper bowl, to 
which the fulcrum and lever are attached ; C } dia- 




phragm ; D, fulcrum ; E, lever, and W, the weight ; the 
pressure under the diaphragm being the power. 

In constructing regulators, sharp edges of the metal 
should not be left to cut the rubber ; the corners of the 
bowls at a should be nicely rounded, and the flanges 
around the edge deep, to give room for the holes, so 
that they would not be too near the inner edge. The 
standard F should not be riveted to the rubber, but 
only rounded on the bottom to lay on it ; nor should 



DRAFT REGULATORS. 



93 



there be holes made in the rubber for any purpose in- 
side of the holes in the flanges. 

Common flat rubber does not make a good dia- 
phragm ; it should be of extra good quality, and thick, 
and dished to fit the bowls ; so that when inflated, there 
will be no tension on the rubber. 

Some makers leave off the upper bowl, using only a 
flange ; but better practice uses one, for it is impossible 
then for over-pressure to burst it, when supported by 
the iron over its whole extent. 

In the construction of a diaphragm for high pressure, 
which will not burst, it is necessary that a very small 
portion of the surface of the rubber should be unsup- 
ported at any time ; and that the movement should be 
small, to admit of using a compound lever with an 
ordinary weight. 




Fig. 33 shows a high pressure draft regulator, with a 
compound lever, in which a very small movement of 
the disk, A, will give 6 inches or so at the end of the 
lever, at B, without straining the rubber in the least ; 



94 STEAM HEATING FOR BUILDINGS. 

the slackness at C forming a concentric corrugation, 
which admits of all the movement necessary. 

83. In connecting diaphragms with the boiler, it is 
best to take the pipe from the water space, as shown in 
Fig. 27, at C ; but when that cannot be done, it may be 
taken from the boiler dome, or any other convenient 
place, except tapping a pipe, which already has a 
"draft" on it (rapid passage of steam through it); for 
in order to prevent irregularities of pressure, it is neces- 
sary to have the initial pressure constantly under the 
rubber. 

When it is necessary to take a steam pipe to a dia- 
phragm, instead of a water pipe, the pipe must be trap- 
ped in such a manner that it will fill with water, and 
the capacity of the trap must be greater than the bowls 
of the diaphragm ; so the water that has filled the trap 
and cooled therein, when it is pressed forward, will be 
sufficient to more than fill the bowls, thus always in- 
suring cold water on the rubber. 

Some will not put a valve in a diaphragm pipe in a 
private house, fearing it may be shut off by some med- 
dler ; but this is a matter which must be left to the 
judgment of the fitter. A very good way is to use not 
less than a § pipe, and immediately under the regulator 
plug the pipe with iron, and bore a T 3 f inch hole 
through the plug. This hole will pass the water rap- 
idly enough for the regulator, and in case the rubber 
should burst, the flow of hot water would not be large. 

When the rubber is fitted in the bowls without ten- 
sion, it very seldom gets holes in it, and will give warn- 
ing by leaking first, but should it be tight it will give 
way suddenly. 

84. When regulators are attached to ash-pit doors, or 



DRAFT REGULATORS. 95 

to extra draft-doors, set in one side of the ash-pit (leav- 
ing the door-proper for the removal of the ashes only), 
the chain is fastened to the end of the lever marked G, 
and to the door ; care being taken in placing the regu- 
lator so that the chain will have a direct pull, and not 
interfere with the opening of other doors. "When a 
regulator is attached to the fire-door, the other end of 
the lever should be used, and this regulator is set a 
pound or so stronger than the draft-door regulator. 

It is not a good plan to make one regulator do both 
duties, by using each end of the lever, as the doors work 
too close together, and a waste of fuel is the result, by 
letting cold air through the furnace frequently ; the in- 
tention being not to open the fire door, unless as a last 
resort. 

85. Doors for regulators should be set at an angle of 
about 45 deg. When a door hangs perpendicularly (with 
the hinges on the top, usual in such doors), the leverage 
changes, as the door swings from the perpendicular, 
throwing a rapidly increasing weight on the diaphragm ; 
but when the door is on a good angle, the increase is 
not so rapid (the ball being set to partly balance the 
weight of the door, if necessary), and the door is posi- 
tive in its action when closing, being hung on an axis 
further from its center of gravity. 

Doors should be planed to fit perfectly, and hinges 
and edges should be so constructed, that ashes will not 
lodge on or under them, so as to clog them. 



CHAPTEK XII. 



AUTOMATIC WATER FEEDERS. 



86. The water feeders that are attached to low-pres- 
sure heating boilers, are simply regulators, — they have 
no power in themselves to force water into a boiler, and 
must be used in connection with waterworks, or a tank 
near the top of the house ; the head of water supplying 
the requisite power. 

So far, there has been but one description of automa- 




tic water feeder, used in connection with steam-heating, 
and though different makers modify the shape and the 
valve, the principle is the same. Fig 34 is a very good 
9G 



AUTOMATIC WATER FEEDERS. 97 

representation, in which A is a cast iron case of suit- 
able design ; B, a copper float, with buoyancy enough 
for the work, and sufficiently thick, so it will not collapse 
with the pressure ; E, a lever, made of brass, to admit 
of bending; F, a fulcrum, and G, a valve, formed with 
a piece of hard rubber, inserted in the end of the lever, 
in connection with the nozzle H t which is usually of 
brass. 

Copper floats in boilers under high pressure, nearly 
always collapse ; but for low pressure, they have been 
constructed to stand very well, though occasionally they 
fill with water, when not well made. 

Hollow copper ball floats are usually made of two 
pieces of copper hammered into hemispheres, and 
brazed together. If they could be hammered after 
brazing, they could be made very strong ; but as the 
reverse is the case, and the heating to redness makes 
them very soft, there is nothing for the artificer to do 
but make them as thick as he can, without impairing 
their floating power. In the brazing of a ball together, 
it is necessary to leave a vent hole in one hemisphere, 
until the joint is thoroughly brazed, and then plug it 
up. A very good way to make floats for regulators, 
since they require some kind of a boss to fasten the 
lever to, is to put a boss on the inside of the hemi- 
sphere, as shown at a, and bore a small hole through 
it, having the thread for the lever tapped tapering; 
this hole will answer for a vent while brazing, and 
when ready to be fastened to the lever, the thread in 
the boss and the thread on the end of the lever can be 
tinned with soft solder, and screwed together cold, 
which will make a perfectly water-tight joint, and not 
leave a partial vacuum in the ball, as would happen if 



98 STEAM HEATING FOB BUILDINGS. 

the ball was closed in the fire, and this vacuum would 
form a factor, not generally taken into consideration, 
which will materially add to the pressure it is subject 
to in a low pressure boiler. 

There is one point in the construction of water 
feeders which requires particular attention, — namely, the 
size of the hole in the nozzle H, which forms the valve. 
This hole should be small, and the higher the pressure 
of the water works, the smaller should be the hole. It 
will be seen by looking at the figure, that the float is 
the power and the force of water the weight, and by in- 
creasing the area of the hole in H, the weight can be 
made to overcome the power. A J of an inch hole is 
usually sufficient to admit all the water required ; but 
if a larger hole is wanted, care should be taken that 
the ball has a preponderance ; otherwise the valve will 
not set firmly to its seat, and the leakage will fill the 
boiler and prove a source of annoyance. This should 
be guarded against, for though it is not dangerous, it is 
disagreeable, and many fitters prefer to leave the feeder 
off on that account, since a straw, or the least dirt, 
will make it inoperative, and flood the boiler in conse- 
quence. 

87. When there are steam-traps to any part of the 
apparatus, which do not return all the water directly 
into the boiler, the water-feeder should be put on, un- 
less there is some one constantly in attendance. With a 
return gravity apparatus it may, however, be dispensed 
with, for the operator, by looking at the water once a 
day, and letting in a supply when necessary, is a better 
reliance. A positive open and shut feeder, under all 
circumstances, has yet to be invented. 

88. When a water feeder is used, the upper or steam 



AUTOMATIC WATER FEEDERS. 99 

pipe must not be taken as a branch from another pipe ; 
it must be taken from the top of the boiler, or dome, 
and away from other large pipes. 

Special attention should be paid to the foregoing. A 
case which came under the writer's notice, was of a 
large horizontal boiler, with a water feeder connected 
to the dome, the water pipe entering the regular feed 
pipe ; the feeder had a glass on it, similar to the water 
glass on the front of boilers, and this boiler was fur- 
nished with an extra water glass, connected with the 
front tube sheet, in the ordinary way ; the upper pipe 
being taken from very near the flange. It was noticed 
that the water in the feeder glass, always stood about 
five inches higher than the water in the boiler glass, 
which led to an investigation, and it appeared that the 
water in the front glass was the true level. The upper 
pipe of the feeder was then taken from the dome, and 
tapped into the boiler shell, when both glasses showed 
the same level of water. 

89. This question of draft in pipes is of vast impor- 
tance, and should receive more consideration than is 
usually paid to it, in connection with boiler appur- 
tenances however. 



CHAPTEE XIII. 

AIR VALVES ON RADIATORS. 

90. The usual position for an air valve on a radiator, 
is near the return pipe. 

With high pressure steam the position of the air 
valve is not of as much importance as with low pressure, 
and one that will work with low pressure, will always 
work with high. 

In vertical tube radiators, the valve is generally placed 
high up on one of the pipes, the lower end of which is 
sometimes run down within the base of the heater, to 
very near the bottom, this is done on the assumption 
that the air being heavier than steam, will be the first 
to go out by the air-vent. 

In single chamber heaters, and heaters made of pipes, 
having free passage top and bottom, the air valve is 
often put near the top, the gravity of the air apparently 
not affecting its egress. 

91. The greatest difficulty exists in drawing the air 
from a flat coil, when the return pipe does not run be- 
low the water lines, but permits of live steam entering 
the coil from the lower end, and forcing the air toward 
the middle of the coil. Some steam-fitters put an air 

valve on a return-bend, at a point about ^ the length of 
100 



> 



= 






AIM VALVES ON MADIATOMS. 101 

. M <*jx* ±rom the lower end, but the result is often a 
disappointment. The best way in case of box coils and 
flat coils, is to carry their return pipes below the tvater line 
and any work so piped will never prove troublesome in 
this respect ; for the current of the live steam is always 
from the steam to the return valve. 

The idea of the air always gravitating through the 
steam, and finding the lowest part of a heater composed 
of small pipes, is erroneous, unless the steam is let in 
one top. 

In what is called the atmospheric radiator, the steam 
enters on top, with a hole near the bottom to let the 
air out, and a drain to carry off the condensation in the 
bottom. Steam enters this radiator through a very 
small pipe, with a nicely graduated valve, which admits 
any desired quantity of steam, and which fills doivnward, 
and permits a part, or the whole of the heating surface of 
the radiator to be used. It may be likened to a balloon 
partially filled with gas, the gas always remaining in 
the top.* 

With system "No. 2," low pressure steam piping, 
there is never any trouble to discharge the air, and for 
extremely low pressure (private house heating) it should 
be used. 

Air and steam mix within a heater, to a certain extent 
and at certain pressures ; this mixture being of doubtful 
gravity. 

Steam at the pressure of the atmosphere, and a tem- 
perature of 212° Fahr., has a gravity about one half 
that of air at the pressure of the atmosphere, and a 
temperature of 34° ; but when the air is increased in 

* These heaters cannot be used in a gravity return apparatus. 



102 



STEAM HEATING FOR BUILDINGS. 



temperature about 160° the steam is then about two- 
thirds the gravity of the air. 

92. Air valves are various in design, but may be 
separated into three kinds : the old-fashioned pet-cock, 
a compression thumb-screw valve, and the automatic 
air valve. 

The first needs no explanation, and may be used on 
rough work, but should not be used on fine work, for a 
plug cock will not stay tight on steam work, and will 
leak on the floors, and wet the ceilings. 

The second is much used, and is simply a small angle 
valve, with or without a stuffing-box, as shown in Fig. 35. 




The third (the automatic air valve), embraces nearly 
as many designs as there are manufacturers of heating 
apparatus ; but the principle used is the same in each 
instance, viz., the taking advantage of the difference of 
expansion of any two metals that will stand the action 
of steam, one of which has a greater coefliciency of ex- 
pansion than the other ; and in reality becomes a metal- 
lic thermostat, which operates a little valve. 

Fig. 36 shows a simple form of this arrangement ; A, 
being a strip of cast iron ; B, and b, strips of brass, set 
against shoulders on the cast iron, and (7, the valve and 



AIR VALVES ON RADIATORS. 



103 




STEAM HEATING FOR BUILDINGS. 



Fty 3$ 



stem, passing through holes in the bar 
b, and the cast iron A, and screwing 
into the other brass (B). 

When heated above the temperature 
at which they are fitted, the brass ex- 
pands more than the iron and forms 
a bow shape, as shown, and draws the 
valve to its seat ; the dotted lines show 
its normal position. The stem, where 
it screws through the brass B, forms a 
regulator, which can be adjusted with 
a screw driver, applied to a slot in the 
valve. The outside D may be a piece 
of pipe, or a casting, with a boss on the 
side of it, to tap a small pipe into, so 
as to carry the vapor away, if required. 

Fig. 37 is another modification of the 
same principle, but has a point of excel- 
lence worth mentioning, to wit — a 
vapor cup, as seen at a. The center 
stem A has less expansion for the same 
increase of heat than the case B, and 
when it expands, closes the valve ; but, 
as stated, the point most worthy of note 
is the vapor cup. Any condensed 
steam which escapes through the valve 
runs down the small pipe b, and drops 
in the evaporating cup a', which forms 
an annular chamber around the case, 
which is always hot when steam is on 
the radiator. For private houses, and 
offices, this is an advantage, as the es- 
cape from the valve can be regulated so 
as to give any desired moisture to the 
air in a room. 



AIR VALVES ON RADIATORS. 105 

Fig. 38 shows a form in which one metal only (brass) 
can be used, the rods b b not being expanded as much 
as the case A, for the reason they are outside, and not 
in direct contact with the steam. When the case A ex- 
pands, it presses on the thumb-screw (7, forming a valve. 

93. There is still another kind of air-vent used which 
is simply a small-chambered fitting, with a very small 
hole bored in it, which always remains open and is 
attached to a radiator in the ordinary way. Where the 
pressure does not exceed 1 lb. above atmosphere it 
may be used ; but for high pressure it will not answer, 
for the waste may be very great, since a hole -^\ 
of an inch in diameter is capable of passing about 
1 lb. of steam in 33 minutes at 50 lbs. pressure ; which 
from 100 vents in 24 hours would be more than two tons 
of water." 

* The above is a theoretical computation based on the flow of steam 
through a theoretical orifice, when no allowance is made for friction 
in so many little holes, which might reduce it one half, but even then 
it is so considerable that attention must be drawn to it. 



CHAPTEE XIV. 

PIPE. 

94. There are two kinds of wrought iron, steam and 
gas pipe — namely, lap-welded and butt-welded. 

There is no lap- welded pipe smaller than 1| inch, 
though butt- welded pipe is made of all sizes, excepting 
extremely large sizes. 

Lap-welded pipe is considered the best, although for 
sizes smaller than two inches it makes little difference 
which is used, if the butt-welded pipes are pro]3erly 
made. 

The butt- welded pipe is the most uniform in size, 
and generally works easier, as it is softer. 

All the pipe and all fittings made in the United 
States and Canada are supposed to be of standard 
dimensions ; so the whole is interchangeable. 

Occasionally in old buildings pipe is found, which is 
known as " old gauge," which is somewhat larger than 
the pipe now in use. 

95. The size of pipe is standard, but the standard is 
arbitrary ; the inside diameter being nearest the nomi- 
nal size of the pipe, which it always somewhat exceeds ; 
small sizes are most disproportioned (as can be seen 
by reference to the table of " Standard Dimensions of 
Wrought-iron Pipe," or to the diagram of sizes of pipe). 

The threads on the ends of pipes should taper T V of 
an inch for an inch in length of thread. 

106 



PIPE. 



107 



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108 



STEAM HEATING FOR BUILDINGS. 



DIAGRAM OF CROSS-SECTION OF WROUGHT IRON PIPE. 




RELATIVE AREAS OP PIPES. 

97. The young steam-fitter has not always a just 
conception of how the size of one pipe compares with 



PIPE. 



109 



that of another ; not knowing how rapidly the area of a 
pipe increases with an increase of diameter. 

When the diameter of a pipe is doubled, the area has 
increased fourfold, and if one having ] the diameter of 
another, it has but T V °f ^ s area. Thus, the area of the 
cross sections of circular pipes are to each other, as the 
squares of their diameters. 

As circles and squares always bear the same relative 
proportions to each other, and as either can be likened 
to the cross section of a pipe, the beginner can always 
find the number of times, the area one pipe will divide 
that of another, by making a square (a!) and calling the 
side of it the diameter of the smallest j)ipe ; then 
around the smaller square construct a larger one, the 
side of it being the diameter of the larger pipe, with 
the corner b forming a common corner for both squares. 
Thus, if the square a represents a 1-inch pipe, and 
you draw around it a square 3J inches on the side, 
and lay the larger square off into squares, the size of 
the smaller one, as shown, the h 
number of the whole squares and 
the sum of the parts of the squares 
within the larger square, is the 
number of times a 1-inch pipe will 
go into a 3 1 -inch pipe. 

It will be seen, there are nine 
whole squares, six half squares, 
and one quarter square, which equals 12J squares : the 
number of times a 1-inch pipe will go into a 3.7-inch 
pipe. 

To prove the above according to the rule — "Pipes 
are to each other as the squares of their diameters," 
square the smaller pipe for a divisor, and the larger 




HO STEAM HEATING FOB BUILDINGS. 

pipe for a dividend, and the quotient will be the num- 
ber of times. 
Example : 





1x1=1. 




3.5 X 

3.5 

175 
105 

l.)12.25(12.25— Ans. 


Ex. 


— To find how 


many 


times a f-inch pipe will go 


into 2 


l 2-inch pipe. 








.75 X 
.75 

375 
525 




2 x 

2. 

.5625)4.0000(7.11— Ans. 
3.9375 




.5625 




6250 
5625 

6250 

5625 
625 + 


98. 


The following 


table. 


has been calculated for the 


use of the steam and 


gas-fitter. 



PIPE. 



Ill 



« 


t^ 


E 








p 


ED 


« 


H 


< 


o 


p 




^ 


© 


5 


g 


3D 


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ft 


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c 


O 


DO 


1 


< 


H 


H 


— 


<J 


~ 


H 


* 


> 


^ 


H 




J 




H 


Q 


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ifie 




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IIjO 1th 


da 






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1 


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1 1 1 1 


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° 


t- 


30 



112 



STEAM HEATING FOR BUILDINGS. 



To use the table. — Find the size of the smaller pipe, 
in the left-hand column, and follow it to the right, until 
it is under the size of the larger pipe, or vice versa ; the 
number thus found is the times the small pipe will go 
into the large one. 

99. The following diagram also illustrates, almost at 
a glance, the relative proportions of pipes, from one 
inch to twelve inches in diameter : the column of figures 
being the diameters of the pipes in inches. 

A DIAGRAM OF RELATIVE AREAS OF PIPES, FROM 1 TO 12 INCHES, SHOW- 
ING THE INCREASED AREA FOR each INCH OF INCREASE OF DIAMETER. 




The 1-inch pipe is represented by one triangle ; the 
triangle immediately opposite the figure. 

The 2-inch pipe is represented by four triangles ; 
the three immediately opposite the figure and the one 
above it. 

The 3-inch pipe is represented by nine triangles; 



PIPE. 113 

the five immediately opposite, and all above it : and so 
on to the end. 

The sum of the triangles immediately opposite the 
size of a pipe, and all the triangles above it, gives tho 
square of the diameter in inches. 

The number of triangles, immediately opposite the 
size of a pipe, gives the increase in units of size (the 
unit being the area of a 1-inch pipe) over the pipe 
next smaller than it ; and the number of triangles, op- 
posite the size of a pipe, with all above it, as far as 
the size of any other pipe, gives the increase in units 
for the difference between the two sizes. 

It will also be seen, that the increase of the area of 
pipes, for each inch of increase of diameter, is an arith- 
metical progression, whose common difference is tvx> 9 the 
first term being one. 

EXPANSION OF PIPES. 

100. In running pipe, for any purpose, special atten- 
tion must be given to its expansion or contraction, for 
nearly all leaks which occur after work is completed and 
tight, if not due to defective material, are caused by ex- 
pansion or contraction, which has not been provided 
for. 

"When a main pipe is run close to a wall, and branches 
taken through holes in the wall, the holes being just 
sufficient for the branches to pass, the latter break off, 
when heated ; but if branches are taken the other way 
across the room, the branches being unconfined, near 
the main, even though confined near their farther ends, 
the spring of the pipe, especially if it is of small diameter, 
will admit of the expansion or contraction of the main 
8 



114 STEAM HEATING FOR BUILDINGS. 

in the direction of its own length. But the branches 
should not be confined in the direction of their length, 
or they will shove the main out of line, and should a 
branch start, directly opposite to a branch so confined, 
it will either be pushed out of position, or broken. 

Main pipes, to look well, must be straight; and 
should be hung so it will expand, in the direction of 
its length, avoiding all the side motion possible, and 
throwing the expansion of the branches in the direc- 
tion of their own lengths. 

Long mains should never be run very close to a wall 
up which risers go ; for the risers admit of very little 
lateral movement, and all the linear expansion of the 
main will be thrown on the riser-connection in the form 
of torsion. 

"When a main is turned with its branch Tees looking 
up, a nipple and elbow can be screwed in to the Tee, so 
as to get any desired angle in running to the wall or else- 
where, and this nipple and elbow, with the pipe from 
the elbow, will admit of more torsion than a straight 
pipe ; and in extreme cases the threads of the nipple 
will turn a little, and prevent anything from breaking. 

Special attention should be given to pipes laid be- 
tween floors, or when they have to cut into floor joists 
or beams. They must not be confined at their ends 
and their branches for 3 or 4 feet from where they 
leave a Tee, and should have room enough to allow for 
the greatest difference of length possible. 

101. It is common for steam-fitters to run their 
return pipes around cellars and basements before the 
concreting is done, and to allow them to be buried 
and cemented into this mass, which becomes as one 
stone, and for a time (when they do not give out upon the 



PIPE. 115 

first warming up) must actually overcome the elasticity 
of the iron ; but it more frequently breaks or leaks, 
either by shoving through the threads of the fittings, 
or else pulling them apart ; or the branches break off, 
by having a large pipe, which may not be confined at 
one end, forced past them. 

102. There is another reason, why pipes should not 
be buried in floors, — namely, lime with moisture destroys 
them rapidly. Work so hid from observation, is the first 
to give out. If connections around boilers, pump con- 
nections, and the like, were kept above the floor, they 
would wear the boiler out. 

103. When hot water or steam has to be carried 
under ground, it must be conveyed in wrought-iron 
pipe, with screwed joints, or cast-iron pipe, with flanged 
joints ; hub and spigot pipes with leaded joints are not 
suitable, for it is impossible to keep them tight when 
subjected to much difference of temperature, as the lead 
expands in a different ratio from the iron, and takes a 
permanent set with comparatively little pressure. 

Cast-iron gas or water pipes, put down in the streets, 
with leaded joints, will compensate in the joints, by 
slipping ; the difference on a twelve-foot length being 
about the ^h f an i nc h f or a difference in tempera- 
ture of 20 degrees. 

104. The steam-fitter should avoid using expansion 
joints (slip joints) when it is possible to compensate in 
any other way. In private houses and single city 
buildings it can always be avoided by taking advantage 
of right angle turns ; but frequently in long runs of 
pipe, in narrow passages and with pipe of large dia- 
meter, they must be used, as spring bends cannot be 
used unless they have considerable length, and a four 



116 



STEAM HEATING FOR BUILDINGS. 



or five-foot turn, on a 6-inch pipe, if the expansion 
was one inch, would be very liable to make mischief. 
An eight-foot turn, on a 2-inch pipe 100 feet long, 
will compensate for any difference of temperature that 
may take place, with ordinary ranges of pressure ; but 
on a 3-inch pipe it would in all probability break, 
assuming that the long run of pipe is prevented from 
springing sidewise. 

Sometimes in running pipe through long, straight 
passages, if the passages have a width of about 6 feet, 
by frequently crossing from side to side, we obtain a 
beneficial result ; especially if it is a return pipe. The 
objection to this method for a steam pipe is the great 
number of turns which would be required for a pipe 
larger than 2 inches ; but when passages make one or 
two right angle turns, nothing can be better where the 
pipe is hung, and has not to pull or push its own 
weight over rough surfaces ; the length of pipe each 
way from the elbow not being sensible of any torsion. 

105. When several boilers are connected together 
between their domes or ends, the connections should 
not be run " short across " from dome to dome. The 




pipes should be run back, or forward, from the domes, 
3 to 6 feet, and then, connected across. 



PIPE. 



117 



The reason of this is plain, when we consider that 
settling of brickwork, or the expansion of the pipes, 
will suffice to throw the weight of the boilers on rigid 
connections. For the same reasons, pipes passing 
through the brickwork of boilers should not rest in the 
walls, but have large holes, covered with loose flanges, 
around the pipes. 

Figs. 39 and 40 show plans of boiler connections, 
when using expansion joints, and when the expansion 




is provided for by spring, the latter being the most 
permanent way, when properly done. 

By reference to the figures it will also be seen, that a 
slip joint only provides for a linear contraction or ex- 
pansion, or a' twisting motion, and does not compensate 
for a difference in level. 

Fig. 41 shows distant rigid objects connected by a 
pipe, in which the expansion is provided for by the 
use of spring hends. 

The expanding power of a 2-inch pipe, when heated 



118 



STEAM HEATING FOE BUILDINGS. 



to the temperature of 100 pounds of steam, exerts a 
force sufficient to move 25 tons. 

106. Cast iron expands one one hundred and sixty- 
two thousandths (-nrsVinr) of its length for each degree 
Fahrenheit it is subjected to within ordinary limits, 




while in the solid state. Its expansion is less than 
wrought iron. 

107. Wrought-iron pipe expands the one one hundred 
and fifty thousandths (tWooo) of its length, for each 
degree Fahr. it is subjected to within any limits, it can 
be used by the steam-fitter ; and the length of the pipe 
in inches, multiplied by the number of degrees it is 
heated, and divided by 150,000, will give the expansion 
for that difference in temperature in inches, or frac- 
tions of an inch. 

Example. — Find what the length of a one hundred feet 
of pipe will be, when heated to the temperature of 100 
pounds of steam, its initial temperature being zero. 

ft. in. in. temp. 

Thus, 100 x 12 = 1200 x 338° = 405600 -r- 150000 = 2.70 
inches. (See table.) 



PIPE. 



119 



108.* — A TABLE OF LINEAR EXPANSION, OF WROUGHT AND CAST IRON 
PIPES (TO WITHIN THE t £o OF AN INCH), FOR EACH 100 FEET IN LENGTH, 
AT TEMPERATURES AND PRESSURES MOST FREQUENTLY REQUIRED BY THE 
STEAM-FITTER. 

WROUGHT IRON. 



Temperature of 


Length of 

pipe when 

fitted. 


Length of pipe when heated to 


the Air, when the 
pipe is fitted. 


215° or 1 lb. 
of steam. 


265° or 25 lbs. 
of steam. 


297° or 50 lbs. 
of steam. 


338° or 100 
lbs. of steam. 


Degrees, Fahr. 


Feet. 


Feet. Ins. 


Feet. Ins. 


Feet. Ins. 


Feet. Ins. 



32 
64 


100 
100 
100 


100 1.72 
100 1.47 
100 1.21 


100 2.12 
100 1.78 
100 1.61 


100 2.31 
100 2.12 
100 1.86 


100 2.70 
100 2.45 
100 2.19 



CAST IRON, 




32 
64 


100 
100 
100 


100 1.59 
100 1.36 
100 1.12 


100 1.96 
100 1.65 
100 1.43 


100 2.20 
100 1.96 
100 1.73 


100 2.50 

100 2.27 

'100 2.00 



* Calculated for Regnault's temperatures and Lavoissier and Laplace's 
difference of expansion. 



CHAPTEE XV. 

SIZE OF MAIN PIPES. 

109. No heating apparatus is perfect, unless it heats 
thoroughly at all pressures ; unless the water of con- 
densation runs back and into the boiler at all pressures ; 
unless it is noiseless under all ordinary conditions, and 
unless the duty of the person in charge is simply to 
take care of the fires, and see there is always sufficient 
water in the boilers. 

As this book is principally devoted to the heating of 
buildings and blocks, which have their own boilers, 
situated either in the building or near to them, the 
formula mentioned below is intended for determining 
the size of main pipes for gravity apparatus, for all 
ranges of pressure or where an early initial pressure is 
required, as with an automatic direct return steam-trap. 

The fitter, in all probability, knows that a gravity ap- 
paratus requires the largest pipes ; thus, he can take it 
for granted, the size sufficient for such will be enough 
for any other description of work. 

110. "With high-pressure steam, which is allowed to 
expand through a building, and eventually escape 
through atmospheric traps, a very much smaller piping 
will do ; but the waste of heat is sometimes enormous 

120 



SIZE OF MAIN PIPES. 121 

with traps which discharge into an open tank, or atmos- 
phere. The difference in favor of a gravity apparatus, 
or apparatus working properly, with direct return traps, 
can always be estimated at 15 per cent., over apparatus 
which permits the water to escape, and thus either 
loses it, or obtains it by pumping it back : and when 
traps are neglected (which is the rule), it may reach 30 
per cent, of all the heat. 

This is not an assertion in the interest of direct return, 
or one which cannot be verified, as the following will 
show. 

When water is returned to the boiler, at a tempera- 
ture of 180° (the ordinary temperature of water from 
gravity apparatus), it requires 1,000 heat units to make 
one pound of it — a pound of steam ; and in condensing 
it to water again and returning it to the boiler at 180°, 
it loses just 1,000 heat units : which have all been utilized 
within the building. Thus every unit of heat, added to 
the water, has been realized, and it represents the maxi- 
mum economy possible in steam heeding ; the power re- 
quired to put the water back being at a minimum — i. e., 
gravity. In the case of an apparatus that ivastcs its re- 
turn water, and has to pump water from the water- 
works at a temperature of 40°, it has to add to every 
pound of water converted to steam, 1,140 units, and gets 
only 1,000 from it, when the water is cooled to 180° (a 
very low temperature by the way for ordinary traps to 
expel water at). Thus, for every 1,140 units added to 
the water, 140 are lost, or over 12^ per cent. When the 
pressure in the radiator is 40 pounds, and the water, 
passing the trap at a temperature corresponding to 
that pressure (285° Fahr.), is allowed to waste— there 
are 1,140 units required to raise fresh water at a mean 



122 STEAM HEATING FOB BUILDINGS. 

temperature to steam : and only 902, utilized in cool- 
ing to 285°, the temperature of water at 40 lbs., which 
leaves 245 units unaccounted for, — or a loss of more 
than 21^ per cent. : and this does not take into consid- 
eration the heat lost in pumping water into the boiler. 

111. The power necessary to put a pound of water 
into a boiler against 70 lbs. pressure, is greater than 160 

foot pounds, and requires one-third of a horse power for 
a cubic foot. As a cubic foot of water evaporated in a 
boiler, and used in a common engine at medium high 
pressure, does work equal to 1,980,000 foot pounds, it is 
evident it requires T J F of a pound of steam to put one 
pound of water into a boiler, the equivalent of a loss of 
about 5.5 heat units to every pound of water returned 
mechanically — assuming the condensation, is pumped 
into the boiler without loss of heat, other than its latent 
heat — but which in practice reaches about 1 per cent. 

112. If the water from traps, discharging at 40 pounds 
pressure, is saved in a tank, and pumped into the boiler 
again, then the condensed water, after being received into 
the tank, will have a temperature of about 200°. But it 
will be said the water escaping from a trap at 40 pounds 
pressure had a temperature of 285°, hence the water 
should be received at that temperature. Since it is 
necessary to have a tank open to the atmosphere (with 
either an overflow pipe or a vapor pipe), to receive the 
water ; and water at a pressure of the atmosphere can- 
not have a temperature above 212°, the difference 
escaping in vapor, or low pressure steam, through the 
vapor pipe ; and if you have a tight tank without traps, 
you must have as large pipes very nearly, to get water 
to gravitate to the tank, as are required for the boiler, 
so that when the difference of level will permit, it is 



SIZE OF MAIN PIPES. 123 

better to put it direct into the boiler. But to return : the 
temperature of the water in the open tank we will take at 
200, and to raise a pound of it to steam, will require 
979 units, and 894 units of it will be realized in cooling 
if it passes the trap at a temperature corresponding to 
40 pounds, the difference being lost into the atmosphere 
by getting into a condition fit to remain in the tank — 
this is over 8 J- per cent., to which add 1 per cent, for 
pumping the water back, which will equal 9i per cent.; 
but should the water be lost each time and fresh cold 
water be supplied it will equal 21| per cent. 

113. Thus it will be seen, it is poor economy to use 
small pipes, and resort to tanks, traps, pumps and 
other contrivances, to get water back, when the price of 
a steam pump expended on larger pipe is frequently 
sufficient to get the water back, and obtain an effect, 
which so far as the heating surface is concerned, will 
give the maximum duty, and do away with one source 
of continual expense, as well as the loss of heat occa- 
sioned by such irregular means. Twenty years ago it 
was excusable, because it was not then generally known 
that water could be returned at all pressures ; but now 
it is unpardonable, when the circumstances of the case, 
position of building, etc., will admit of doing better. 
Furthermore, it should be the duty of the architect to 
provide, if possible, for direct-return, in the general 
planning of buildings. 

114. There is no definite rule amongst those who 
attempt steam heating, by which they may determine 
the correct size of pipes ; hence much confusion and 
many failures occur, to the general injury of the trade. 
Those who make a specialty of heating, soon find they 
must use large pipes, and they generally adopt some 



124 STEAM HEATING FOR BUILDINGS. 

arbitrary unit, such as to allow the size of a |-inch pipe 
to each radiator ; a half a square inch in the cross 
section of the main to each 100 square feet of heating 
surface, or to each radiator ; and the area of a one-inch 
pipe to each 100 square feet of heating surface ; which 
latter the writer has adopted, after passing successively 
through each of the others. 

This latter rule also compares very nearly with de- 
ductions made from the steam pipes of certain build- 
ings throughout the country, which are considered 
representative pieces of work, and have proved them- 
selves ample, when the greatest cold prevailed. 

When the distributing pipes are to be covered with 
some good non-conducting material, the surface of 
them may not be figured as against their size, but 
when they are excessively long, or exposed in their 
own surface, it should be considered ; more especially 
when the pipe is less than 3 inches in diameter, since 
a small pipe has a very much greater surface, com- 
pared to the volume of steam than a large one ; and 
this must be allowed for in calculating. 

115. Thus, the area of a one-inch steam pipe, .7854 of 
a square inch, may be taken as the unit ; and it serves 
very well, as by simply squaring the diameter of a 
pipe in inches, you have the number of 1-inch pipes, 
or units, or hundreds of square feet, of pipe or plate 
surface, the main pipe will supply steam for. Thus a 
3-inch pipe will supply steam for 900 square feet of 
heating surface. 

116. There is another reason why the area of a one- 
inch pipe (.7854 of a square inch), as the arbitrary 
unit, is more satisfactory than a square inch ; namely, 
the increase of the diameter of a steam pipe, is directly 



SIZE OF MAIN PIPES. 



125 



as the square root of the heating surface ; and according 
to the arbitrary unit here adopted, the diameter of the 
'pipe in inches, is exactly one-tenth of the square root of 
the heating surface in feet. Thus, when you find your 
heating surface, extract its square root, in feet, and call 
one-tenth of it the diameter of the main, in inches. 




EXPLANATION OP DIAGRAM. 



117. The above diagram has been made to illustrate 
this formula at a glance, and give the size of main pipes 
for surfaces, from 100 to 10,000 square feet. 

The ordinates of the curve, A B, correspond to the 



126 STEAM HEATING FOR BUILDINGS. 

square feet of heating surface in the column marked 
A B ; and the perpendicular dotted lines, which express 
the size of the pipe, in inches, correspond with the 
curve opposite the numbers in the column, which ex- 
press square feet of heating surface. 

The ordinates of the curve G D bear the same relation 
to the column CD as the curve A B bears to the column 
A B, and shows the size of pipe for heating surfaces 
from 1,000 to 10,000 square feet. 

It will be seen that, 1,000 at the head of the column 
A B corresponds to 1,000 at the bottom of the column 
C D, and the ordinates of both curves agree near the 
3-inch pipe line. 

Example. — Eequired the size pipe, for 600 square 
feet of heating surface. Find 600 in the column, and 
follow the horizontal line to where it crosses the curve 
A B ; then follow the nearest perpendicular line to the 
nearest size of standard pipe above the line, in case it 
should not come exactly on a standard size ; in this 
case it is a little below 2 1 -inch pipe, which size should 
be taken. 

Less than a 1 1 -inch pipe should not be used hori- 
zontally in a main, unless for a single radiator connec- 
tion. 

If this rule is used to determine the size of the 
steam pipe in radiator connections, increase the pipe one 
size, to give them a practical magnitude, to overcome 
loss by short turns, etc. Main pipes should not de- 
crease in size, according to the area of their branches, 
but should be proportioned by the same rule as for 
determining the size of the main the first time. The 
same is true of the large branches. Find what they 
have to supply steam for, and proportion them as you 



SIZE OF MAIN PIPES. 127 

would a main, figuring their own surface as radiating 
surface unless they are to be covered. 

Occasionally steam has to be carried long distances to 
a dozen or so large radiators, as in a railroad depot, or 
in one or two story buildings, which cover much 
ground. In a case of this kind, it would be well to 
increase the diameter of the pipe, one or two sizes, to 
provide for loss by friction, etc., but in high buildings 
fully heated this will not be necessary, unless the 
pipes pass through cold hall-ways, or are unusually 
exposed. 



CHAPTEE XVI. 

STEAM. 

118. Tempeeatuees of steam according to the different 
formulae, all agree at the atmospheric pressure, but as 
the pressures become high, they vary slightly : Reg- 
nault and Rankine are nearly alike, while the experi- 
ments of the Franklin Institute are about five degrees 
higher for 75 lbs. apparent pressure. 

119. The technical terms, used about steam by writers, 
and the expressions in vogue amongst steam-fitters, 
want some explanation to make them clear, as many of 
them are synonymous and the fitter does not always know 
what is meant. 

Pressure — Is the force of steam, usually expressed in 
pounds per square inch, and " elastic force " ; " expan- 
sive force " ; " tension," and " elasticity," are synonyms. 

Temperature. — The heat of steam, usually expressed in 
English and American books in degrees of Fahrenheit's 
scale.* 

Density. — The weight of a cubic foot of steam, com- 
pared to a cubic foot of water. Syn. — Weight of water 
in steam. 



* The use of Centigrade and Reaumur scales and foreign weights and 
measures, are very much to be condemned in English reading books or 
papers for practical men, the reduction to familiar terms often requir- 
ing more mental effort than the problem to be solved. 

128 



STEAM. 129 

Maximum density of steam. — The proper quantity of 
water in the steam, suitable to the pressure, i. e. when 
the steam is neither superheated nor laden with par- 
ticles of water mechanically. Syns. — Dry saturated 
steam ; dry steam. 

Superheated steam. — Expanded by heat, or an increase 
of pressure by heat, without the addition of water. 

Wet steam. — Water carried up into the steam by for^e 
of ebullition, and held in the steam by the rapidity of 
evolution, when the steam space of a boiler is not 
large enough. Syn. — Saturated steam. 

Foaming. — A condition differing from wet or saturat- 
ed steam, by having an excess of some foreign sub- 
stance in the water, causing it to seem lathery and 
which appears to give the water in the boiler a tem- 
perature above what would be due to the pressure, by 
retarding the separation of the steam, and raising the 
whole mass of water into a froth. Syns. — Priming ; 
drawing water. 

Priming in a boiler is effected by two causes — viz.: 
Taking away the steam in intermittent puffs, faster 
than it is made and foaming. Priming in boilers is 
generally an effect : foaming a cause. 

Volume. — The space occupied by a given quantity of 
water, should the water be converted into steam, the 
relative volume decreases as the pressure increases. 
Syns. — Eelative volume ; bulk for bulk. 

Specific gravity of steam. — The iveight of its bulk, 
compared to the same bulk of water, air, or any other 
substance it is contrasted with. Syn. — Density. 

Specific heat of steam. — The heat of a given iveight, 
compared to a given iveight of air, iron, or any other 
substance it is contrasted with. 



130 



STEAM HEATING FOR BUILDINGS. 



120. The annexed table gives the apparent pressure 

of steam from atmosphere to 100 lbs. in pounds per 

square inch ; absolute pressures in inches of mercury, 

and temperatures in degrees Fahrenheit (to within one 

half degree), according to Regnault, the volume being 

calculated. 

TABLE NO. 5. 



ELASTIC FORCE, TEMPERATURE AND VOLUME OF STEAM. 



ELASTIC FORCE. 


Temperature 
of Steam 


RELATIVE VOLUME 


Average Rise of 








Temperature 


Apparent 
Pressure of 
Steam in lbs. 
per Square 


Absolute 

Pressure in 

Inches of Mer- 


corresponding 
to its Press- 
ure. 


Bulk of Steam 

compared to Bulk 

of Water. 


for one lb. 
Pressure for 
each 10 lbs. 


Inch. 


cury. 











30.0 


212.0 


1710.0 


■\ 


1 


32.03 


215.5 


1612.0 




2 


34.07 


219.0 


1523.0 




3 


36.11 


222.0 


1442.0 




4 


38.15 


225.0 


1372.0 




5 


40.18 


227.5 


1312.0 


-2.8 


6 


42.22 


230.0 


1248.0 




7 


44.27 


232.5 


1194.0 




8 


46.30 


235.0 


1168.0 




9 


48.33 


237.5 


1103.0 




10 


50.37 


240.0 


1061.0 




11 




242.0 




< 


12 




244.0 






13 




246 






14 


.... 


248.0 






15 


60.56 


250.0 


*895.0 


1.75 


16 




252.0 




17 




253.5 






18 




254.5 






19 




256.0 






20 


70.' 75 


257.5 


' 718.0 




21 




259.0 






22 


.... 


260.5 






23 




262.0 






24 




263.5 


'766.O 




25 


80:91 


265.0 


684.0 


►1.5 


26 




266.5 






27 




268.0 






28 




269.5 







29 




271.0 






30 


9i!l2 


272.5 


'614.0 





STEAM. 
TABLE No. 5— Continued. 



131 



ELASTIC FOHCE. 




RELATIVE VOLUME 








Temperature 
of Steam 




Average Pise of 








Temperature 


Apparent. 

Pressure of 

Steam in lbs. 

per Square 


Absolute 

Pressure in 

Inches of Mer- 


corresponding 
to its Press- 
ure. 


Bulk of Steam 

compared to Bulk 

of Water. 


for one lb. 
Pressure for 
each 10 lbs. 


Inch. 


cury. 








31 




274.0 




> 


32 




275.5 






33 




277.0 






34 




278.5 






35 


loilsi 


279.5 


'558. 


J.1.3 


36 




280.0 






37 




282.0 






38 




283.0 






39 




284.5 






40 


lii.'s 


285.5 


- 5l6 


J 


41 




286.5 






42 




288.0 






43 




289.0 




► 1.15 


44 




290.0 




45 


12±.*7 


291.0 


'470. 




50 


131.88 


297.0 


435. 




55 

60 


152." 25 


302.0 
307.0 


390. 


[1.. 


65 

70 


172! 43 


311.0 
315.0 


343. 


| 0.8 


75 




320.0 




[0.8 


80 


193] 6 


323.0 


*305. 


85 




327.0 




j-0.7 


90 


213! 38 


331.0 


*283. 


95 
100 


233 !7G 


334.0 
337.5 


'260. 


-0.65 



121. When the pressure in inches of mercury is not 
given, multiply the apparent pressure in pounds per 
square inch by 2.0376, and the answer will be the 
inches of mercury above atmosphere; or that which an 
old fashioned mercury column would show. 

Example.— lOlbs. x 2.0376 = 20.376 inches of mer- 
cury. 

If the absolute pressure is required, add 30 to the 
above. (20.37 + 30 = 50.37. See table.) 



132 STEAM HEATING FOB BUILDINGS. 

"When the volume of steam is not given, add 459 to 
the temperature of the steam ; multiply the product by 
76.5, and divide by the absolute pressure in inches of 
mercury; the answer is the volume, or number of cubic 
feet, a cubic foot of water will occupy when made into 
steam at the pressure required. 

Example. — Required the volume for 10 pounds press- 
ure, temperature 240° Fahr. — 240 + 59 = 699 x 76.5 = 
53473.50+50.37=1061.9 (see table). 

To find what a cubic foot of steam will weigh at dif- 
ferent pressures, divide 1000 by the volume, correspond- 
ing to the required pressure, and the answer will be the 
weight in ounces. 

Example. — What *^ill a cubic foot of steam at maxi- 
mum density weigh, at 40 lbs. per square inch. — Vol- 
ume 510+1000=1.96 oz. 

To find the number of cubic feet of steam a pound of 
water will make at the different pressures. — Divide the 
weight of a cubic foot in ounces (as above) into 16, and 
the answer will be the volume in cubic feet to the pound. 

Example. — How many cubic feet of steam, at 20 lbs. 
pressure, will one pound of water make. — Volume 
718 + 1000 = 1.39 + 16.0 = 11.5 cubic feet to the pound 
of water. (See Diagram of dry saturated steam.) 

To find the weight of steam necessary to raise a given 
quantity of water a certain number of degrees. — Sub- 
tract the lowest temperature of the water from that to 
which it is to be heated for a dividend, — subtract the 
highest temperature of the water, from 1147 for a di- 
visor, and the quotient from these will be the weight of 
the steam compared to the weight of water. 



STEAM. 



133 



Example. — Find the weight of steam necessary to 
raise water from 75° to 190°.— Thus 190°- 75°= 115, for 
a dividend 01147-190= 957, divisor 0-957 ~ 115 = 12 
or jVV the weight of the water. 

To find the weight of water, a given weight of steam 
will heat. — Proceed as above, only transpose the divisor 
and dividend. 



p 



rcssuve 



7?z Lis Per £ yua-re -T?zc?i sZlozse J2 £?no£p-h eye 




Example.— 115 ~ 957= 8.32 times the weight of the 
steam. 

122. The above diagram of Kanldne's formula has 
been modified to commence at the atmospheric pressure 
— 15.7 of the absolute scale being one pound here, and 
shows at a glance the cubic feet of steam to the pound 
weight of water, at the different pressures, as well as 
the temperatures, corresponding to the pressure. 



CHAPTEK XVII. 

HEAT OF STEAM. 

123. The unit of heat is the raising the temperature 
of one pound (16 oz.) of water one degree Fahrenheit, and 
is the standard measure of values used in all calcula- 
tions pertaining to heat. 

The equivalent in force of the unit of heat, is the rais- 
ing of 772 pounds avoirdupois, one foot high, and is 
called the mechanical equivalent of heat. 

The equivalent of the unit of heat in the warming of 
air, is 48 cubic feet of dry air, raised one degree in 
temperature.* 

124 Sensible and latent heat. — Steam has a tempera- 
ture corresponding to its pressure, as given in the table, 
and that apparent temperature is known as the sensible 
heat of steam ; but it is found that steam contains more 
heat than a thermometer will show ; heat that can be 
made manifest in the warming of air, water, etc., warm- 
ing a very much larger quantity than would appear by 
a comparison of the temperature of the steam, with the 



* In calculations made on the air of drying rooms, etc., the weight of 
water vaporized must be nrovided for, as so much water converted into 
steam. 

134 



HEAT OF STEAM. 135 

ordinary temperatures of water, and this extra heat, 
which is not seosible to the thermometer, is called latent 
heat of steam. 

When a solid becomes a liquid, or a liquid becomes a 
vapor, heat is absorbed, more than was necessary to 
raise it to the temperature of conversion, and this latent 
heat does work in the destruction of the force of cohe- 
sion and other occult changes which take place, and 
must be absorbed/rom some other substance. In the case 
of steam in a boiler, it comes from the fuel during com- 
bustion, and when a pool of water is vaporized in the 
street, it comes from the sun directly, and from the 
earth, air, etc., indirectly. When steam or vapor is con- 
densed, this same quantity of heat that was received — 
no matter where, is again given off to any substance 
within its influence, air, water, etc., colder than itself, 
and it is this property, to convey more heat within ordi- 
nary controlable temperatures, than any other substance 
which makes water and its vapor so valuable.* 

It takes as much heat to melt a pound of snow from a 
temperature of 32°, to water at 32°, as would warm a 
pound of water from 72° to 212°. This heat is ab- 
sorbed by the water in changing from a solid to a 
liquid, and must be given off again before the water 
could be frozen. 

From the temperature of ice, to 212° under the press- 
ure of the atmosphere, there is no heat made latent in 
confinement, the water receiving only 180° of heat ; but 
in the conversion of one pound of water at 212°, to 
steam at 212°, it receives 966 more units of heat : enough 
to warm 5 J pounds of water from 32° to 212°, or to cool 

* Water has the greatest specific heat of any known substance. 



136 STEAM HEATING FOR BUILDINGS. 

9 pounds of iron from redness to zero. And this heat is 
the latent heat, and the real thermal value of the steam. 

The sum of the sensible and latent heat of steam, is 
nearly the same for all pressures. At atmosphere, the 
sensible heat is 212°, and the latent 966°.6 = 1178°.6 as 
the total heat ; at 100 pounds the sensible heat is 337.5, 
and the latent 8748, equalling 1212.3 as the total heat ; 
the difference being 33.7, but this difference is not mani- 
fest in the heating of water when the steam is allowed to 
expand to atmospheric pressure in cooling, for it expends 
itself in force, which would be manifest in an engine, 
and account for the "startling discovery" of Mr. Holly, 
when he asserts " The power is taken out, and the heat 
left in the steam ; and that every unit of heat that left 
the boiler, remained in it (the steam) as long as it was 
steam at any pressure." (Pages 25 and 26, circular of 
1880.) This is a mistake. Steam allowed to expand to 
its full volume against atmosphere, exerts nearly the 
same force as if expanded against the piston of an en- 
gine — plus the loss by radiation, etc. 

Actually, the heat is carried out of the boiler ; being 
another form of heat made latent, the extra units remain- 
ing in the steam in the form of force, which a little cal- 
culation will show, though it falls short of the actual 
theoretical duty, being 26,000 foot pounds, when the 
difference is 33.7 units. 

Hence the assertion — the total heat of steam is the same 
for all pressures, is correct in making calculations on 
warming, as it is presumed the steam is expanded to at- 
mosphere in using ; the total heat, however, according to 
the experiments of Eegnault, increases as the pressure 
advances. 

The annexed diagram has been constructed from the 



HEAT OF STEAM. 



137 






U- 






tables of Eegnault, to show tlie 
increase of lie at, above the con- 
stant 1146.6, which is usually 
taken as the sum of the heat of 
steam — from 32° upwards. 

It also shows the number of 
units in latent and sensible heat 
of steam, compared with each 
other ; the ordinates of the curve 
A B showing the sensible heat, 
from one pound pressure to 200, 
counting from the line marked 
zero, or counting from any other 
imaginary line, as 32° (ice), or 
from the line E F, which may 
be taken as the temperature of 
return water. The difference 
between ordinates of the curve 
A B, and the curve C D, gives 
the latent heat of steam for the 
different pressures noted. The 
difference between the ordinates 
of the curve G D, and the con- 
stant line 1146.6, shows the in- 
crease of the sum of the heat, 
above the constant 1146.6. 

125. A pound of water con- 
verted to vapor in the open air, 
or a pound of water vaporized 
from clothing in the drying 
room, requires very nearly the 
same heat as would bo required 
to evaporate one pound of water 
to steam, in a boiler; and for 



138 STEAM HEATING FOR BUILDINGS. 

all practical calculations it can be taken as the same. 
Thus, the weight of steam necessary to dry clothing, or 
to evaporate water, in any kind of cooking apparatus, 
etc., can never be less than the weight of the water driven 
off ; and of necessity, it will be greater to supply the 
loss by radiation, or in warming the fresh air of a drying 
room (which must be changed as often as it becomes 
saturated), and from other causes. 

126. Equivalents of heat. 

The heat necessary to warm a pound of water at mean 
temperature (39° Fahr.) one degree {the heat unit), will 
warm three and three-quarter pounds of air, one degree ; 
2 T V pounds of vapor of water, one degree ; 9 pounds 
of iron, one degree, and very nearly 2 pounds of ice, 
one degree.* 

The heat necessary to convert one pound of water 
from the temperature of feed water, or return water, 
at 178°, to steam at one pound pressure (or to any press- 
ure not noting the slight increase for high pressures), 
is 1,000 heat units, and will heat 48,000 cubic feet of 
dry air one degree ; or 4,800 cubic feet of air 10 degrees ; 
or 480 cubic feet of air 100 degrees, making no allow- 
ance for the expansion of the air, which will increase 
the bulk T \- for a difference of 100 degrees ; in other 
words, the 480 cubic feet will be increased to 583 when 
heated 100 degrees, and the 4,800 will be increased 
to 4,920 or ^V of its bulk for a rise of temperature of 
10 degrees. 

The heat necessary to warm one cubic foot of water, 
from the temperature of the return water to steam, is 

* It must not be confounded with melting the ice, but refers to 
changing the temperature of ice below 82°. 



HEAT OF STEAM. 139 

capable of warming 41,000 cubic feet of dry air from zero 
to 72°, but if the air absorbs 5 grains of vapor of water 
for each cubic foot — as from clothes in a drying room, it 
will be equivalent to the fall of the temperature of the 
air to 37.8, but if the moisture is already in the air, and 
has only to be warmed (superheated), it will not be equal 
to the cooling of it, one and a half degree. 

One grain of water vaporized is equivalent to cooling 
from 6.86 to 7.2 cubic feet of air one degree according to 
the initial temperature, and is a constant ; but 1,000 
grains of vapor already in the air, warmed any number 
of degrees, cools 3 J r to 4 cubic feet of the air the same 
number of degrees. 

When water is evaporated at the expense of the heat 
of the air, it makes a large factor, which cannot be over- 
looked ; but vapor already in the air, when warmed 
along with the air, forms a small factor and is not of 
much practical consequence. 



CHAPTEE XVIII. 

AIR. 

127. Aie is a mixture whose parts are not chemically 
combined : consisting of 77 per cent, of nitrogen, and 23 
per cent, of oxygen, by weight, when considered pure, i. e. 
when it is in the conditon best suited to support animal 
life. It also contains about ^Vo °f its volume of car- 
bonic acid gas and some watery vapor, and is capable 
of absorbing any other gas, or vapor, to a certain extent, 
distributing them throughout the whole atmosphere, by 
what is called the law of gaseous diffusion — a property 
which gases have of mixing and diluting, which prevents 
gases of the most opposite specific gravities from strati- 
fying for any considerable time. Prof. Youmans says, 
— This effect will be produced even through a mem- 
brane of india-rubber; carbonic acid gas rising and 
mixing with hydrogen, though twenty times heavier. 
Thus exhaled air, and air contaminated in any other 
way, is perpetually made respirable by diffusion. 

This property is of the utmost importance to air, 
for if its elements were to become separated, or the 
addition of a noxious gas to remain separated from the 
mass, death would be the result in all unventilated 
houses in a very few hours. It frequently happens in 
mines, and wells, where the entrance is small, and there 
are not sufficient disturbing influences, that poisonous 

140 



AIR. 141 

gases become abundant, the diffusion being too slow 
for the generation of the deleterious gas. 

In confinement, air may have its oxygen increased or 
diminished ; an increase of 2 or 3 per cent, causing fever, 
and a diminution of 3 per cent, causing death, if the 
carbonic acid gas from the lungs is exhaled into such 
air and the air inhaled afterward. 

128. The amount of fresh air necessary for respira- 
tion for an adult, is stated to be about 300 cubic feet in 
24 hours, meaning fresh air which had no specific con- 
tamination ; but as air in rooms is likely to be breathed 
again, in a more or less degree, and as it is vitiated by 
moisture from the skin and lungs, and by other means 
well known to people of ordinary intelligence, 300 cubic 
feet per hour should be little enough to provide for in 
ordinary ventilating, not with the expectation of keeping 
the air absolutely pure ; but to keep it in a state of 
dilution, which will not be injurious, if it receives no 
other contamination than that from the body in health. 

Hospitals should be supplied with ventilating appar- 
atus capable of supplying 3,000 cubic feet of air per 
hour to each patient ; with means to double or quadruple 
the quantity by forcing it (as with a fan) in times of 
contagious disease, or in very warm weather. 

An ordinary kerosene lamp destroys about 40 cubic 
feet of air in an hour, possibly as much as two persons 
would use. 

129. Air, assumed as unity, is taken as the standard 
of weight of gases, when its temperature is 60° Fahr 
and the barometer 30 inches. 

Air for the same weight, at a temperature of 34°, oc- 
cupies 827|> times the space water does ; a cubic foot 
weighing 527 troy grains. 



142 STEAM HEATING FOR BUILDINGS. 

At the temperature of 32°, 13J cubic feet of air 
weighs (a few grains over) one pound avoirdupois, which 
increases to 14J, 14 T V, and 15J, for 60, 70 and 100 
degrees respectively. 

130. The expansion of air is nearly uniform at all 
temperatures, expanding about T ^ of its bulk at 32°, and 
for each increase of one degree in temperature. Regnault 
putting it a little less, while Dr. Dalton puts it as high 
as 4J3, and other authorities have put it at T ^ : any of 
these formulae being near enough for small differences 
of temperature. 

The following table will show the increase or de- 
crease, of one thousand cubic feet of air at a tempera- 
ture of 32°, when the expansion is ¥ ^o« 



Temperature ... 20'—, 
Volume 895, 

Temperature ... 32° + , 
Volume 1000, 

Temperature . . . 70° + , 
Volume 1077.5, 

To compute the volume for other temperatures, its 
volume at 32° being unity, use the following — 

Rule. — Divide the difference between 32° and the re- 
quired temperature by 490 ; to the answer add one 
(whole number), if the required temperature is above 
32°, but if it is below, subtract it from one and multiply 
the volume of air at 32, by it. 

Example. — Find the volume a thousand cubic feet of 
air at 32° will be at 212°.— Thus, 212° -32°- 180°-- 490 
=0-367 + 10=l-367x 1000 + 1367-0 cubic feet. 



TABLE NO. 


G. 






10°-, 
914, 


Zero. 
0, 10°+, 

935, 953, 


20° + 
975, 


40° + , 
1017, 




50° + , 
103G, 


60° + 
1057, 


80° + , 
1098, 




90° + , 
1128, 


100° + 
1139. 



AIR. 



143 



To find what a volume of air at 70 will be at 40. — 
Multiply the volume by the number corresponding to 
40, and divide by the number corresponding to 70. 

To find what a volume at 40 will be at 70. — Multiply 
by the number corresponding to 70, and divide by the 
number corresponding to 40. 

Example. — Eequired what a volume of 3417-0 cubic 
feet of air at 100° will be at 50°.— Thus, 3417 x 1036 = 
3539988.0-r- 1139.0 = 3108.0 cubic feet. 

The following table is copied from a text-book, and 
given as Dr. Daltons'; though it does not agree with 
that which is given as his difference of expansion ; it 
agrees very nearly with other tables which are given jis 
his. It shows the increase of bulk from 75° to 680° 
when the volume at 32° is 1,000. 

TABLE NO. 7. 



Fabr. 


Bulk. 


Fahr. 


Bulk. 


Temp. 75 


...1099 


Temp 


97 


....1146 




' 76 Summer heat . . 


....1101 


« 


98 


....1148 




< 77 


....1104 


<< 


99 


....1150 




< 78 


...1103 


(< 


100 


....1153 




< 79 


...1108 


(< 


110 


....1173 




< 80 


....1110 


" 


120 


....1194 




1 81 


....1112 


« 


130 


....1215 




1 82 


...1114 


tt 


140 


....1253 




1 83 


...1116 


tt 


150 


....1255 




1 84 


....1118 


It 


160 


....1275 




< 85 


...1121 


tt 


170 


....1295 




' 86 


....1123 


a 


180 


....1315 




1 87 


...1125 


it 


190 


....1334 




' 88 


...1128 


a 


200 


....1364 




' 89 


....1130 


n 


210 


....1372 




" 90 


....1132 


tt 


212 Water boils... 


....1375 




1 91 


...1134 


" 


302 


....1558 




< 93 


...1136 


tt 


392 


....1739 




" 93 


....1138 


" 


482 


....1919 




" 94 


...1140 


" 


572 


....2098 




" 95 


...1142 


tt 


680 


....2312 




" 96 


...1144 









144 8TB AM HEATING FOB BUILDINGS. 



WATEKY VAPOB IN THE ATMOSPHEKE. 

131. Air is capable of holding a certain quantity of 
vapor of water, or any other condensable vapor, in solu- 
tion, so to speak — the proportion depending on the 
temperature of the air. The warmer it is, the larger 
quantity it will hold, and as it becomes cool again, it 
deposits it, or forms clouds or fog, which condense on 
anything colder than the air ; leaving the air upon 
raising its temperature, capable of taking up more 
moisture, to be again deposited in dew or rain. It is 
this property of air which gives it its drying qualities. 

The atmosphere is seldom laden with moisture to its 
utmost, and is still capable of taking up more moisture ; 
this difference being its drying poicer, which is going on, 
in a more or less degree, at all temperatures. 

132. An absolutely dry atmosphere is an almost im- 
possibility. The coldest air contains some moisture, but 
it is not always possible to tell how much, as air is seldom 
saturated to its maximum ; so to find the quantity of 
water, air at a certain temperature is capable of taking 
up, a quantity of the air must be cooled until the mois- 
ture becomes apparent — forming a dew point — when a 
knowledge of the quantity of moisture already in the 
air can be had from tables (the result of experiments of 
Dr. Dalton and others, who have made a study of the 
hygrometric state of the atmosphere) which give the 
greatest quantity of vapor the air is capable of contain- 
ing, for the different temperatures. Thus, if air is 
cooled from 70 to 50, and shows condensation at the latter 
point, all the moisture the air is capable of taking up for 
70 is the difference between the quantities of vapor at 
those temperatures in the table. 



AIR. 



145 



133. The drying power of air, which enters a drying- 
room, is therefore, the difference between the maximum 
saturation for the highest temperature of the oat, and its 
deiu-point before its enters. 

The object in introducing this subject, and giving the 
following table of the quantities of vapor, air is capable 
of taking up, is to show the great economy there is in 
time, and some saving in heat, by having the highest 
possible heat in a drying room, that will not injure the 
goods or materials to be dried. 

TABLE NO. 8. 

134. — A TABLE OF THE QUANTITY OF VAPOR OF WATER WHICH AIR IS 
CAPABLE OF ABSORBING TO THE POINT OF MAXIMUM SATURATION, IN grains 
PER CUBIC FOOT FOR VARIOUS TEMPERATURES. 



Degrees Fahr. 


Grains in a cubic 
foot. 


Degrees Fahr. 


Grains in a cubic 
foot. 


10 


11 


85 


12-43 


15 


1-31 


90 


14-38 


20 


1-56 


95 


16-60 


25 


1-85 


100* 


19 12 


30 


219 


105 


22-0 


32 


235 


110 


25-5 


35 


2-50 


115 


30-0 


40 


306 


130 


42-5 


45 


3G1 


141 


58-0 


50 


4-24 


157 


85-0 


55 


4-07 


170 


112 5 


GO 


5-82 


179 


138-0 


G5 


6-81 


188 


1660 


70 


7-94 


195 


194-0 


75 


924 


212 


265-0 


80 


10-73 







* Up to 100 degrees the table has been copied from the Encyclopaedia 
Britannica, where the full table to 100, advanffing by degrees, can be 
found. Beyond 100 degrees the table has been calculated from the 
elastic force of vapors according to Regnault, and are approximately 
correct. 

10 



146 STEAM HEATING FOB BUILDINGS. 

135. It will be seen by a study of the table, that the 
quantity of vapor, per cubic foot of air, increases very 
rapidly as the temperature advances — a common differ- 
ence of about 25 degrees in the rise in temperature of 
the air, doubling the quantity of moisture it is able to 
take up. Hence, all other things being equal, an in- 
crease in temperature of 25 degrees in a drying-room 
will reduce the time for drying one half, and an increase 
of 50 degrees will reduce the time to one-fourth, and so 
on in that geometrical ratio. 

The saving in heat, is not so apparent, as it takes just 
so much heat to vaporize a certain quantity of water, 
and the quantity of heat is a constant. But there is a 
saving, in not having to heat the air, and the moisture 
it contains from its initial temperature, so many times 
as compared to the amount of moisture carried off ; in 
other words, the amount of heat necessary to evaporate 
the moisture will be the same for all temperatures, but 
the quantity of heat lost in the application is less, for 
the air can be moved more slowly and kept in contact 
with the materials longer, or until it is fully saturated, 
and its desiccating power is apparent to the last. This 
is especially true in drying woods, as the high heat icill 
penetrate wood and expel moisture, even when the air is not 
capable of holding any more moisture in suspension. 

THE COST OF VENTILATION. 

136. A house 40 x 40 ft. is warmed and ventilated in 
two stories. Each story is 11 feet in the clear, making 
33,600 cubic feet, and it is desirable to change the air in 
the house once in each hour, which is ample to maintain 
a very pure atmosphere. In order to know its cost, a 



AIB. 147 

business man would proceed to figure in the following 
way : The steam-heater has told him the apparatus 
put in, would convert between 10 to 12 pounds of the 
return water to steam, at an expenditure of one pound 
of coal (a pretty high average) ; consequently, the next 
thing to know is, ivJiat is the equivalent of 1 lb. of coal 
in the warming of air. Now it is admitted that a cubic 
foot of water, losing one degree of its heat, will warm 
3,000 cubic feet of air one degree, and that one pound of 
it, will warm 48 cubic feet of air one degree ; but in con- 
verting the pound of water to steam, it absorbs heat, 
equivalent to warming it 1,000 degrees, which, of course, 
is equivalent to warming 48 cubic feet of air 1,000 de- 
grees, or 480 cubic feet 100 degrees, or 4,800 cubic feet 10 
degrees.* Thus the fact is established, that a pound of 
steam returned to water, will warm 4,800 cubic feet of air 
10 degrees ; but it is not so well established that the coal 
evaporates 10 to 12 times its own iccight of icater from 
the temperature of the return. If the water was return- 
ed at 180° Fahr. and the coal the best, 14 pounds of the 
water, converted to steam, would be the greatest possi- 
ble theoretical quantity ; but 11 to 12 has been attained 
in practice, though it is not common, 8 to 10 being ordin- 
ary for house boilers. So, for the sake of safety, and to 



* The quantity of air, water or steam, will warm, is figured according 
to the specific heat of each, for the same weight. Approximately, water 
requires 3f times as much heat to warm a given weight of it, any num- 
ber of degrees, than the same weight of air ; but as air occupies 827-i- 
times the space water docs, for the same weight, it will have to be mul- 
tiplied by this factor (relative volumes), and by the heat. — Thus, 
1 x 827.5 = 827.5 x 3.75 — 3103. As air contains a little moisture, which 
must be warmed also, the odd 103 may be dropped, and is usually fig- 
ured at 3000. 



148 STEAM HEATING FOR BUILDINGS. 

get the price as high as the poorest practice would make 
it, he takes only one-half the theoretical quantity and 
figure it at 7 pounds of water to the pound of coal. Thus 
we have 4800 x 7 — 33000 cubic feet of air, which can be 
warmed 10 degrees by one pound of coal. But it ap- 
pears that 10 pounds of coal have been burned per hour, 
a quantity sufficient to warm 33,600 cubic feet of air 100 
degrees. Whence, then, is this apparent discrepancy? 
Assume air outside to be 20° Fahr., and as it passes the 
heat registers it has a temperature of 120 degrees, having 
been warmed, just 100 degrees, in passing through the in- 
direct radiator ; but an examination of the air, as it goes 
out at the ventilating register, shows its temperature to be 
70, which would suggest 50 degrees of the heat had been 
utilized in the rooms, in maintaining the temperature, 
and the other 50 had escaped through the ventilator, 
and been lost as heat ; but it has produced ventilation, 
and the movement of the air. Now, the ventilating 
flues aggregate 2 square feet of cross section, and the 
air, as it escapes, has a velocity of 5 feet per second in 
the middle of the flues, and which, if it were not for the 
friction of the sides, would pass 36,000 cubic feet in an 
hour. Making some allowance for friction, we will say 
33,600 cubic feet of air passes in an hour, exactly the 
cubic contents of the part of the house, ventilated ; tak- 
ing one half of all the heat with it, or what represents 
5 lbs. of the coal burned in the hour. 

Thus the ventilation of a good home can be thorough- 
ly done for lj cent per hour, when coal cost 5 dollars 
per ton, less than 3£ cents per 100. M. cubic feet of air 
moved under conditions, which all preponderate against 
the price ; the difference of temperature between the in- 
side and outside being 50 degrees, which is a high average. 



AIR. 149 

There seems to be a simple relation, between the 
amount of heat necessary to maintain the temperature 
in a room, and the amount passed off in ventilation, no 
matter at what temperature the air passes the register 
entering the room, in indirect heating. 

For instance, let air enter at 20, and instead of rais- 
ing its temperature to 120, it is raised to 95 as it passes 
into the room. The difference between the temperature 
of the room (70°) and 95 and 120, is as 1 and 2. Thus, 
if the windows, etc., cool a certain quantity of the air, 
from 120 to 70, they will cool twice that quantity from 
95 to 70, to maintain the same heat, and twice the quantity 
of air will have to pass out through the ventilator at 
half the greater difference, to make room for the fresh 
supply necessary to keep up the heat. So, the temper- 
ature at which air passes through the heat registers (of 
the same building) only affects the quantity of air moved 
and not the heat. 

This also points to another result — namely, the less 
the difference between the temperature the air leaves 
the heat register at, and the temperature the room is 
to be maintained at (so long as it proves sufficient), the 
more air there must be passed in a given time to keep 
the required warmth : which will of necessity make the 
air purer. 

A huilding heated altogether by indirect radiation, cannot 
be other than sufficiently ventilated. 




CHAPTEE XIX. 

HIGH PRESSURE STEAM USED EXPANSIVELY IN 
PIPES FOR HEATING. 

137. It has been customary, when speaking of steam- 
heating apparatus, to divide them into two kinds — 
called respectively high and low pressure ; but these 
names cannot now be accepted in their literal meaning, 
any more than high and low pressure would express 
the difference between non-condensing and condensing 
engines. 

Very high pressure steam is now used in the gravity 
apparatus, which some years ago was only constructed 
for low pressure steam. At that time, the terms low 
pressure apparatus and gravity apparatus were synony- 
mous; but since the gravity apparatus has been made 
to run at any pressure, the terms gravity system and 
expansion system have become common — to distinguish 
the two principal systems. 

When steam has been let into pipes at any pressure, 
and run arbitrarily, to suit the convenience of one, who 
wants steam at a distance, under the supposition steam 
will run to any place where pipes can be put (as it will 
when certain conditions are complied with), such piping 

150 



HIGH PRESSURE STEAM. 15] 

amongst steam-fitters used to be called high pressure, 
and is now synonymous with " expansion system," or 
steam used expansively for heating. 

The conditions alluded to are : the steam must be 
allowed to expand, — to blow through in fact ; if the 
pipes are not run on some system, that provides for the 
taking away of the water, at every low point in the 
piping ; and the quantity of steam used in a given time, 
must be sufficient to carry along the icater of condensation 
which forms in the pipe during transmission. 

Scattered buildings, heated from one source, must be 
heated in this way ; if they have no basements, and are 
on different levels, and the condensed water must be 
taken care of by steam traps. 

It is usually attended with considerable waste of heat 
from imperfect steam-traps, etc., and requires the con- 
stant vigilance of the engineer, and should not be used 
in single buildings, when it is possible to make a gravity 
apparatus. 

138. Lately, Mr. Holly has brought this system before 
the public on a large scale — the heating of towns and 
cities ; but it is only the old system on a larger and 
grander scale. Instead of heating three or four build- 
ings from one source, he heats hundreds. 

The magnitude of the apparatus prevents any attempt 
to take back the condensed water, which of necessity is 
wasted after it is cooled to its utmost practical limit ; 
and as the water becomes the property of the consumer it 
can be used in the house for culinary purposes, and in the 
laundry, if tlie rust from wrought iron pipe, carried along 
with the water, will not discolor clothes. 

The following quotation is from the Holly circular 
and explains the system in their own words : 



152 STEAM HEATING FOR BUILDINGS. 

" THE MECHANICAL DETAILS 

of this system we will present briefly, by detailing the course 
of the steam from the boilers through the various devices to 
control and regulate its use until it is finally condensed into 
pure distilled 

WATER FOR DOMESTIC PURPOSES. 

ec In this system of heating it is desirable to have as few 
plants as possible placed at central points, as convenient as 
may le, to coal and water. As the profit to those who 
supply the steam will depend upon its economical produc- 
tion, it will become of the first importance to admit nothing 
known to modern engineering art that will secure the largest 
amount of evaporation of water, at a minimum cost for coal, 
as steam is used merely as 

A CARRIER OF HEAT. 

" It is of course unnecessary to say, that the best and most 
economical boilers should be selected, and the most careful 
and competent engineers and assistants obtained. It is by 
no means an unimportant fact to be considered by cities with 
reference to this system, that the dangers and annoyances of 
boilers will be confined to a few localities, and their object- 
ionable features obviated in cities like New York, St. Louis 
and Cincinnati, where thousands of boilers are distributed 
through the city. 

" From the boilers the steam passes into 

THE MAINS AND LATERALS. 

The material used after experiments with cast iron and 
other substances, is the ordinary lap-welded, ivrought iron 



HIQE PRESSURE STEA3I. 153 

steam-pipe. These are always tested by the manufacturers 
to a tension far above any possible use, for example : a 12- 
inch pipe of this kind J-inch thick, has a tensile strength 
of CO, COO lbs., and would bear a pressure of 2,500 lbs. to the 
square inch, as no pressure exceeding 100 lbs. will ever be 
required in this system. 

"DANGER FROM EXPLOSION 

of pipes can never become a subject for discussion, but con- 
densation is. For unless steam can be transmitted to con- 
siderable distances without too great loss by condensation, 
all devices to use it in buildings, however ingenious, would 
of course be useless. Condensation being caused by the radi- 
ation of heat from the pipes, the 

SUGGESTION OF COMMON SENSE 

would be to arrest the radiation, that is, keep in the heat by 
inclosing the pipes in the best non-conducting material that 
is attainable, and cheap enough. There is nothing new about 
it. Wool, hair, charcoal, brickdust, ashes, plaster, cotton,, 
sawdust, gypsum, etc., have been used in various ways ever 
since metal pipes were used to convey steam. 

' ( The pipe is placed in a lathe and wound about, first, 
with asbestos, followed by hair felting, porous paper, manilla 
paper, finally thin strips of wood laid on lengthwise and the 
whole fastened together by a copper wire wound spirally 
over all. This is thrust into a wooden log, bored to leave an 
intervening air-chamber between the pipe and wood, and of 
sufficient size to leave from three to five inches of wood 
covering. The elasticity of the wrappings permits the free 
expansion and contraction of the pipe irrespective of the 
wood log which is securely anchored and made immovable. 
The whole is placed in a trench a short distance below the 



154 STEAM HEATING FOR BUILDINGS. 

surface without regard to frost. At the bottom of the trench 
is laid an earthen tile drain to carry off any earth moisture, 
and in order further to insure the continuous dryness of the 
wood log inclosing the pipe, if desired, one and one-half 
inch plank are fastened around the log leaving an air space, 
and the whole daubed with coal tar and covered with earth 
never again within the experience of this generation to be 
disturbed. 

"WE SAT NEVEK, 

because the mains are never tapped for the attachment of 
service pipes, as in the case of gas and water mains, and be- 
cause the precautions taken to secure the wood against alter- 
nations of dryness and moisture will, according to experi- 
ence, preserve it indefinitely. 

"Pipes prepared in the manner described have been tho- 
roughly tested, and it is proven beyond doubt that conden- 
sation can be reduced to a point that renders the general 
transmission of steam not only practical, but profitable. At 
the risk of being tedious, we will quote, for the benefit of 
the curious, a well-attested experiment of Mr. Holly. In 
1,600 feet of three-inch pipe, laid on a descending grade of 
20 feet, the lower end trapped for water, steam pressure con- 
stant at 20 pounds at both ends, during 12 hours, water of 
condensation carefully weighed, amounted to 82 pounds per 
hour. The Holly boilers, accurately tested, evaporated 9 
pounds of water per pound of coal. 82 pounds of water 
therefore represented 9 pounds of coal, or 2J per cent. 
More clearly thus : Each pound of steam above 212° con- 
tains 960 units of heat ; the heat units lost in the conden- 
sation of 82 pounds of water were 78. 7-20, or at the rate of 
1.312 units per minute. Now the capacity of a 3-inch 
pipe at 20 pounds pressure is 765 cubic feet per minute, 
containing 27.044 units of heat, of which only 1.312 were 



HIGH PRESSURE STEAM. 155 

lost, viz., 2J per cent. Experiment and practice, since veri- 
fied in 15 cities, show that the most economical pressure to 
be maintained in the mains is from 40 to GO pounds, 
although in some cities 70 pounds has been used. Experi- 
ence with large 'mains is yet limited, 8-inch being the 
largest in use. By calculation, the condensation at GO 
pounds pressure is, in 3-inch pipes, per mile, 2. G ; in G-inch 
pipes, per mile, 2.0; in 12-inch pipes, per mile, 0.7. The 
condensation in large pipes is greater, but the relative per- 
centage less. 

" The experience of Detroit demonstrates the fact that GO 
pounds pressure could be maintained in four miles of 10-inch 
and 6-inch pipes, against the drafts for power and heat 
along the line. The capacity of a 6-inch pipe at 60 pounds 
pressure may be estimated thus : a G-inch pipe at 60 pounds 
pressure will discharge 102 cubic feet per second. A horse- 
power is one cubic foot of water, or 1712 cubic feet of steam, 
or 427 cubic feet of steam per second. Therefore a 6-inch pipe 
at 60 pounds pressure will supply 216 horse-power per mile, 
and the same amount of steam will supply 

3,000 CONSUMERS PER MILE, 

averaging 12,000 cubic feet of air space to be heated. 
"The next serious obstacle was found in the 

EXPANSION AND CONTRACTION 

of metallic pipes between the extremes of temperature, say 
32°, and the heat of steam at 60 lbs. pressure 307°. The 
expansion of wrought iron is -5}^ of its length, about 2 J 
inches in 100 feet. It was the inability to obviate this, that 
defeated the effort to inaugurate a general system of steam- 
heating in European cities. This difficulty was completely 
overcome by 



156 STEAM KEATING FOR BUILDINGS. 



THE JUNCTION AND SERVICE-BOX. 

These are placed at convenient intervals along the line 
of 100 to 200 feet. The arriving-pipe from boilers is in- 
serted by a nickle-plated extension or telescopic joint, made 
steam-tight by passing through a stuffing-box. The de- 
parting pipe is immovably attached to the box, so that 
one end of each 100 feet of pipe is fast and the other 
movable, affording free-play to the expansion and contrac- 
tion. 

" All service-pipes are taken from the junction-box, which 
is securely bolted to the masonry, and anchored to the 
pipes. The bottom of the box being placed lower than 
the pipes, all water of condensation is carried forward and 
deposited in it, to be taken up subsequently as 

ENTRAINED WATER, 

and reconverted into steam, at lower pressure, as the steam 
passes through the reduction valve.* The adjustable hoods 
are for the purpose of regulating the passage of dry or moist 
steam. The junction-box provides for the expansion of 
mains, the attachment of service-pipes and reception of 
water, no water is ever found therefore in the mains, and no 
provisions for trapping off water are required. The boxes 
are accessible by man-holes in the street ; from the junction- 
box, the steam passes to 



* From the above, one is likely to be led to believe— all the so-called 
entrained water flies into steam ; but this is not so ! Only that quantity 
of it is converted into steam at a low pressure, which can be evaporated, 
by the difference of the units of sensible heat of steam for the different 
pressures, which for the difference between 50 pounds and 2 pounds is 
equivalent to the re-evaporating of less than -f 6 of the water condensed 
under the high pressure ; the rest has to be forced through the pipes by 
the passage of the steam. — Remark by the Author. 



HIGH PRESSURE STEAM. 157 



THE REGULATOR 

by means of which the pressure of steam is reduced, and the 
supply to the building regulated automatically. This is ac- 
complished by two diaphragms of rubber packing, acted upon 
by weighted levers, and moving two slide-valves. The first 
valve is weighted to 10 lbs., and the second to 5 lbs., or 2 
lbs. if required. When the steam arrives at the first valve 
of the regulator, it contains, suspended in minute particles, 
all the water which has been condensed in the mains, and 
brought forward to the junction-boxes. This is known as 
entrained water, which, under 60 lbs. pressure, cannot be- 
come steam, but does so at lower pressure of 10 lbs., and any 
further moisture remaining is further converted into steam, at 
a still lower pressure of 3 lbs., thence it passes at a uniform 
pressure through 

THE METER, 

placed, as seen in the plate, above the regulator. It resem- 
bles, and in fact is, the movements of a 55-day Yankee clock; 
as the steam passes, the movements are made to rotate a 
screw, upon which hangs a pointer moving along a dial, 
each revolution registers an arbitrary unit, the value of 
which has been previously ascertained by weighing the 
water. The clock marks the time and registers the quan- 
tity." 



"When one building furnishes steam to several adja- 
cent buildings, or when a cluster of buildings have a 
boiler house, it is not necessary to use junction boxes, 
or even common expansion joints ; the expansion may 
be provided for with right angle turns, or by throwing 
the expansion within the walls of the different buildings. 



158 STEAM HEATING FOR BUILDINGS. 

Comparatively small piping can be used in an expan- 
sion system, and when there is no provision for draining 
the condensed water from the pipes, a size barely suf- 
ficient to carry the required steam along is preferable ; 
as in that case, the draft will carry the water out of the 
pipes ; whereas, if the pipes were larger, the draft of 
the steam would be so slow, the pipes would fill until the 
contracted passage increased the velocity of the steam 
to such a degree it forced itself through in irrgular 
pulsations, and caused pounding. 



CHAPTEE XX. 

EXHAUST STEAM AND ITS VALUE. 

139. Among the many who own steam engines and the 
engineers who run them, there are few who have a just 
appreciation of the thermal value of the clouds of ex- 
haust steam continually blown to the winds from the 
apparently numberless exhaust pipes, which can be 
seen from the top of a high building in any of our 
large cities. 

When I say that three-quarters of the practical thermal 
value of every pound of coal burned in the boiler fur- 
nace, is lost past recovery to the consumer, I am put- 
ting it at less than the actual loss ; and could this heat 
be converted into available motion, suitable for power 
purposes, it would be a boon indeed, and a fortune to 
the one who could do it. Perhaps there is a chance 
for the electrician to convert it into energy ; but as yet 
engineers can use it for heating purposes only, where 
its full value can be shown in the heating of water, air, 
or any tangible substance. 

The first purpose for which the exhaust steam is gen- 
erally employed is to warm the feed water, the object 
being to raise its temperature as high as possible, be- 
fore it enters the boiler, thereby to save fuel. 

159 



160 



STEAM HEATING FOB BUILDINGS. 



140. The first question which nearly always sug- 
gests itself to the engineer is, How hot can feed water 
be made ? The second which he sometimes considers, 
but seldom arrives at a satisfactory conclusion about, is, 
What percentage of the coal does the heating of the 
feed water represent ? and the following, which rarely 
come under his notice, How much of the exhaust steam 
from an engine can be used in heating all the feed water 
necessary to supply the loss caused in the boiler by 
supplying steam to the same engine ? and how much 
of it is left for use elsewhere, partly or wholly, to heat 
the factory in winter or for drying purposes ? 



jFicfM. 




The answer to the first question is: Water under the 
pressure of the atmosphere cannot be heated above 212° 
Fahr., and when the feed water passes the check valve 
at a temperature of 200° it should be considered satis- 
factory, although it is possible to do better. 

Where water is forced -through a heater, the tempera- 
ture can be raised higher than when drawn by a pump, 
from the heater, as the lessening of the pressure also 
lessens the capacity of the water for sensible heat. 

Some makers of feed water heaters claim they can 
heat the water above 212°, because it is under pressure; 



EXHAUST STEA3I AND ITS VALUE. 



161 



but it is evidently a mistake to attempt it, as both the 
water to be heated, and the steam necessary to heat it, 
should have a pressure above atmosphere, and any at- 
tempt to keep a back pressure in the exhaust pipe for 
the simple purpose only of warming the feed water above 
212° is attended with a loss instead of a gain. 

The attempt to heat the feed water 5° above 212° by 
a back pressure of 2 pounds, the mean pressure in the 
cylinder being 50 pounds, is attended with a loss in 
energy, greater by more than five times the gain to 
the feed water. 

The answer to the second question is : That when the 
feed water is raised from mean temperature 39° to 212° 
by the use of the exhaust steam at atmospheric press- 
ure, it is equivalent to very nearly two-thirteenths of 
the weight of the fuel necessary to convert water, at 
mean temperature, to steam at any pressure, and 15-18 
per cent, of the coal is the greatest possible saving that 
can be made for this difference of temperature. 



FlqM 




To find the saving of other differences of temperature 

in the feed water, divide the difference between the 

temperature of the cold water as it enters the Heater 

and that at which it enters the boiler into 1,146, less the 

11 



162 STEAM HEATING FOB BUILDINGS. 

difference between the cold water and 32, and the pro- 
duct is the fraction of the coal heap. 

141. The answer to the third question is : That two- 
elevenths of the exhaust steam is the greatest quantity 
that can be utilized in the warming of the feed water, 
and making a generous allowance for loss by radiation, 
etc., there will still be three-fourths of all the exhaust 
steam for other purposes. 

The next general purpose for which the exhaust steam 
from an engine can be used is in the warming of the air 
of a building, to which purpose it is often applied, though 
not as much as it should be, as there appears to be an idea 
among many users of steam, that it is just as iv ell to take 
live steam from the boiler as to cause one or two pounds 
back pressure on the engine for the purpose of getting 
a circulation, and driving the air from all parts of the 
coils. 

142. The loss in power to an engine from back press- 
ure is very nearly directly as the difference between 
back pressure and mean pressure. Thus, in an engine 
of 50 pounds mean pressure, with a back pressure of 2 
pounds, there is a loss of 4 per cent., and as the available 
energy of an engine cannot represent one-quarter of the 
practical thermal value of the coal, the loss caused by 2 
pounds back pressure can- 
not represent more than 
1 per cent of the coal, and as 
it is an incontrovertible fact 
that the exhaust steam con- 
tains more than three- 
fourths, or 75 per cent, of 
the practical thermal value of the coal, the balance is 
largely in favor of using the exhaust steam. The steam- 




EXHAUST STEAM AND ITS VALUE. 



163 



fitter when preparing to use the exhaust, usually places 
a bach pressure valve in the exhaust pipe, of such con- 
struction, that it can be loaded to suit, so as to reduce 
the back pressure to a minimum, when in use, and to 
hold it open when not required. 

Fig. 42 shows a section of a back pressure valve, 
with the weight hanging on the positive end of the lever, 
showing the position of the valve when the steam is 
turned into the coils. Fig. 43 shows the weight on the 
negative end of the lever, the position usually used in 
summer. Fig. 44 shows cross section on line a b, and 
stuffing-box and spindle. 

143. Exhaust, and live steam, should never be used in 
the same coil at the same time. 
It is often attempted, but is very 
difficult to regulate, and the bet- 
ter way is to make the exhaust 
coils no larger than the steam 
will fill, and should this not 
prove sufficient for the space to 
be heated, add live steam coils, 
with entirely independent con- 
nections. 

Sometimes coils are furnished 
with two sets of connections, 
live and exhaust; but this re- 
quires constant attention to 
prevent workmen, etc., from crossing the steams, 
thereby causing a waste. 

Another objection to having live and exhaust steam 
connections on the same coil, is the style of trapping 
used, for one is not fit for the other. 

A very good way to trap, and provide for the con- 




164 STEAM HEATING FOR BUILDINGS. 

densed water from an exhaust steam coil, is to have an 
inverted water siphon to the sewer or tank, as shown 
in Fig. 45, with a vapor pipe to the roof, to remove an 
excess of pressure and the air. This pipe should have 
a check valve on it, to prevent the return of the air, 
between the strokes of the engine, and the water trap 
should be as deep as possible. 



CHAPTEE XXI. 

BOILING AND COOKING BY STEAM, AND HINTS AS TO 
HOW THE APPARATUS SHOULD BE CONNECTED. 

144. Large institutions with many inmates, find it 
almost impossible to cook without the aid of steam ; 
and manufacturers have long since abandoned all exter- 
nally fired kettles. 

Of the superiority of steam, as a means of drying and 
cooking, there is no question, and the occasional failures 
which occur, should not be attributed to steam, but to 
errors in the construction of apparatus, and an igno- 
rance of their use. Satisfactory appliances are with- 
in the reach of the steam-fitter, though frequently the 
ruinous competition in small things, which compels the 
lowest bidder to neglect and omit everything possible, 
or in other words, " to do the least for the least money" 
ruins the effect of otherwise successful machines. 

The first and commonest kind of cooking by steam, is 
" steaming," which is again divided into steaming in the 
atmosphere (or at atmospheric pressure), and steaming 
under pressure, in closed tanks or boilers. Steaming can 
be used in the preparation of anything into which water 
cannot enter, or become part of, as oils ; or of substances 
which want an addition of water, but are capable of 

165 



166 



STEAM HEATING FOR BUILDINGS. 



taking up only sufficient water to properly prepare 
them ; as vegetables, or substances which want to be 
bleached or disintegrated, as rags. 

The simplest form of steamer is the ordinary kitchen 
steamer ; a wire basket or tin pot with holes in the bot- 
tom of it, suspended in a larger pot with water in the 
bottom of the latter, the water not reaching the bottom 
of the basket, but the steam, rising and mixing with the 
air in the basket, gives a uniform heat, when the water 
in the lower pot is boiling. 

It is well known to the intelligent cook, that vegeta- 
bles cooked this way can be done through without break- 



^.u\',^,|,^^^^^^.^^'.■.^^'A'■'■^^' 




* \¥ 

o o o O o 
o o o o o o ; 
o o o o o 



77T7/ f //iZ j 



ing, or without losing any of their starch. This cannot 
be done in boiling water, as the mechanical action of 
the water during ebullition breaks and washes out part 
of the substances, etc., before they can be sufficiently 
cooked in the center. 
The modification of this simplest kitchen steamer, 



BOILING AND COOKING BY STEAM. 167 

used in large buildings, such as hotels and public insti- 
tutions, is shown in Fig. 46. 

The outside case, A, may be of cast iron, or sheet iron 
riveted and soldered with a cover of sheet iron. The 
baskets, B B, rest inside the outer case, on a perforated 
shelf, (7, and are usually made of heavy tin plate, with 
holes in the bottom for the condensed steam to run off. 

The connections to these steamers require particular 
attention, far more than would appear from a super- 
ficial examination. 

The condensed water which gathers in the bottom of 
the outside case should be carried to the sewer or drain, 
and must be connected in such a way, that the foul air 
of the sewer cannot return into the steamer and con- 
taminate the food. And as much — and more — attention 
must be paid to the waste connection from a vegetable 
steamer, than is paid to the connections from a wash 
basin, even in a sleeping room. It is not only essential 
how the connections are run, but from ichat material 
they are composed, and further, -how the joints are 
made, and from what material. 

As the steam and hot water are capable of destroying 
lead pipes and traps, or working the lead joints out of 
cast iron pipes, it is best to use either wrought iron 
screwed pipe, or cast iron pipe with rust joints ; using a 
very deep S-trap, constructed of fittings, with plugs at 
every corner, so as to get straight openings at every 
part of the pipe, by simply removing the plugs. This 
is necessary to remove grease, or any obstruction that 
may pass into the pipe. The pipes should be of large 
diameter (about 3 ') with the trap sufficiently deep to pre- 
vent the pressure of steam within the steamer, from blow- 
ing it out, and connected with some contrivance, vacuum 



168 STEAM HEATING FOR BUILDINGS. 

valve, or vent pipe, run on approved sanitary principles, 
to prevent its siphoning out, as is common to all soil pipes. 

There is another source of contamination or poison, 
in the connections of vegetable steamers, or any other 
steam boiler, which must have a vapor pipe ; these 
pipes should not be constructed of galvanized iron or 
copper, or any other substance whose salts are poison- 
ous, as the condensation which takes place within this 
vapor pipe, falls back into the kettle, continually wash- 
ing down carbonate or sulphate, or whatever may be 
formed that yields easily to the action of pure water. 
These pipes should be constructed of iron gas pipe, 
with screwed joints, or cast iron pipes, with rust joints. 

The live steam connection to an open steam box, or 
steamer, should be very small. Usually a J or J-inch 
pipe is used, and there is no discretion exercised in the 
manipulation, but an endeavor made to cook as rapidly 
as possible, regardless of steam. Beyond a certain 
quantity of steam admitted, nothing is gained in time, 
as just steam enough to expel the air is all that can be 
used ; a greater supply is only wasted through the 
vapor pipe, or escapes into the kitchen, under the edge 
of the cover. 

There is another point in the construction of open 
steamers worth considering — namely, a water seal 
around the edge of the cover. 

The seal consists of a groove or channel around the 
top edge of the case, into which a rib around the under 
side of the cover fits, as can be seen at a , Fig. 46. 

This seal should be as deep as possible, and to be 
effective should run around the whole cover, and not 
be dispensed with on the side of the hinges, as is fre- 
quently done. 



BOILING AND COOKING BY STEAM. 



169 



The object of this water trap, or seal, is to prevent 
steam from escaping into the kitchen and to force any 
excess of pressure out through the vapor pipe. 

To get the greatest economy, the water seal should be 
two inches or more deep, with a small sized vapor pipe 
with a valve in it, so it can be cJioked down, to hold a 
pressure in the steamer, but not enough to force the 
water seal. 

Steaming under pressure must be done in a closed 
boiler or tight tank, capable of resisting high pressure 
steam. 

A common form of this class of steamers is the rag 
boiler in the paper mill. It is a horizontal cylinder, 




with conical ends, supported on trunions, and made to 
revolve by machinery, so as to use the mechanical 
motion in assisting the disintegration of the rags. This 
boiler is shown in Fig. 47, and should be constructed of 
exceedingly heavy iron, or it may explode, and do much 
injury. The pipe connections are made at the ends of 
the trunions (a'), which are provided with stuffing-boxes 
revolving around the pipe, thus leaving it stationary. 
Another form of high pressure steamer is an upright 



170 



STEAM BEATING EOR BUILDINGS. 



tank of strong construction, in which fats are rendered 
and separated by the action of high pressure steam. 
This tank is shown at Fig. 48, and is 
often 20 to 30 feet long. 

The fats and oils stratify, accord- 
ing to their gravity, with the water 
of condensation underneath, and are 
drawn off at the numerous cocks, 
according to their quality. 

145. The steam connections on 
these tanks are made top and bot- 
tom, and they are sometimes con- 
structed with a spiral coil near the 
bottom. 

Cooking and manufacturing, by 
the transmission of steam heat through 
metal surfaces, and not by direct 
contact, as in steaming, includes ap- 
paratus of varied designs, often the 
result of years of experimenting, the 
following modifications being the 
most common. 

Figs. 49 and 50 show sections of 
two of the ordinary forms of double- 
bottomed steam cooking kettles. 

The various uses to which these kettles are applied 
are wonderful. Differing very little in shape, the size 
alone adapts them to the special use. Small sizes, 20 
to 40 gallons, can be used for glue melting, etc.; sizes 
running from 60 to 100 gallons are mostly used in 
hotels and institutions for cooking meats and farina- 
ceous foods, and larger ones, up to 500 gallons, are 
used in sugar-houses and soap boiling establishments. 




4ftJ2 r U\J 



BOILING AND COOKING BY STEAM. yj\ 

Sizes to 200 gallons are usually cast iron, but larger 
ones are often made of wrought iron, riveted and 
calked. 

The connections to these kettles are plain, but the 
steam pipe should be large, and the return water pipe 
should not be put back into a return gravity circulation 
apparatus, but should be carried away by a good steam 
trap of approved pattern. 

Yapor pipes from these kettles should be of iron, 
for the same reason mentioned in connection with 
"steamers." 




The pipe from the inside of the kettle, which carries 
the contents to a receptacle, or sewer, should be large, 
with tees and plugs at every right angle, instead of 
elbows, to permit of easy and rapid cleaning, should it 
get stopped with grease, or any other substance which 
hardens on cooling. 

In these kettles steam cannot be zuasted unless it is 



172 



STEAM HEATING FOR BUILDINGS. 



passed through a defective steam trap, the consump- 
tion of steam depending on the amount of work to bo 
done, and the radiation from its sides. 

This radiation is often partly prevented by an out- 
side loose jacket, and if the space between the jacket 





and the kettle is filled with some non-conducting ma- 
terial, the loss of heat from the outside of the kettle 
will be reduced to a minimum. 

There is another class of kettles or pans which are 
not double-bottomed, but boil and cook by steam heat 



BOILING AND COOKING BY STEAM. 173 

transmitted through spiral coils, passed around the 
inside of the bottom, the pan itself being partially 
exhausted of atmosphere ; that the contents may boil 
at a temperature much below 212° Fahr. 

These kettles or pans are usually very large, and are 
principally used in sugar-houses and condensed milk 
establishments, or any place where boiling or evaporat- 
ing, at very low temperatures, is a desideratum. 

Fig. 51 shows a section of one of these pans, the 
principal points of importance to the steam-fitter, or 
coppersmith, are the sizes of the pipes, and the manner 
in which they should be run. 

When a quantity of water is to be raised from ordi- 
nary temperatures (35° to 55° Fahr.) to boiling, it must 
be borne in mind by the fitter, or constructor, that it 
will take, in steam, at least -I of the weight of the water 
in the pan, to raise it to the boiling point, and that 
when steam is first turned into the space, between the 
bottoms of jacketed kettles, or into the spiral coils of 
tanks, or vacuum pans, the shrinkage — i. e., condensa- 
tion of the steam, for the greatest difference of tem- 
perature, is something enormous ; and unless the supply 
of steam is continuous, and the pipe which conveys it 
ample for the greatest amount of work that can be put 
on it at any time, the result will be the filling up of the 
space or coil with water. This is caused by the absence 
of pressure of steam through the pipe, coming on the 
surface of the condensed water, to keep it down, and 
under some conditions the vacuum produced actually 
drawing water into the coil, from some other coil or the 
branch return pipes. 

To get a proper result, and economize in time, the 
pipe from the boiler must be sufficiently large, and all 



174 STEAM HEATING FOR BUILDINGS. 

the connections and valves have area enough, to sup- 
ply the greatest quantity of steam required for the 
greatest work. Some have an idea they can waste 
steam, by giving a heating or boiling apparatus a full 
head of steam, but this is a mistake if they have 
proper steam traps, or return into, or are part of a 
return gravity apparatus. For the boiling of water, or 
the heating of air, can only use the steam it can con- 
dense, and the amount of steam used from first to last, 
is the same in any case, plus the loss by radiation for 
the time. 

It is not long coils of small diameter that are re- 
quired, but short coils of large diameter, with large 
piping throughout. 

With small long coils the apparatus, at first, takes 
a considerable time to heat up ; but when it is in 
"train," it seems to do very well. The reason of this 
being plain, when we consider that all the steam re- 
quired to keep a kettle boiling is exactly equal to what 
is given off in steam, from the surface of the water in 
the kettle. 

At first, while the great difference of temperature 
between the water and the steam lasts, the coil is 
warmed a comparatively short distance of its length, 
because all the steam that can pass in a given time, is 
condensed in this first part of the coil, consequently 
the wliole coil is not doing duty, when it should be 
most efficient. 

Many have found that by turning on the steam first, 
and then letting in the water slowly, the kettle was 
boiling by the time it was full, and if they filled it with 
cold water first, it would not boil in an hour. 

Some might reason from this, if their pipe and coil 



BOILING AND COOKING BY STEAM. 175 

were large enough to pass sufficient steam to boil the 
water in 15 minutes, by passing it in slowly, it should 
boil the whole in the same time, since it takes the 
same quantity of steam to boil a cubic foot of water, no 
matter how it is applied ; that this is not correct, as far 
as the size of the pipe is concerned, the following will 
show : 

In the first case, where the water is let in slowly, the 
coil or space is hot, and the quantity of water not being 
enough at any one time to condense the steam faster 
than it can pass, the whole coil is doing duty during 
the whole time. But when the large body of water is 
acted on by the steam, the latter rushes into the coil 
and is immediately condensed, filling the coil with water, 
the greatest part of its length, and leaving the first 
short heated part of the coil, to boil the water in the 
kettle, before the pressure of steam will pass through, 
to keep down the water of condensation. 

Many again think, this condensed water will run off 
by its own gravity ; but this is not so, as it cannot run 
off unless there is a pressure on its surface equal to 
the pressure of the atmosphere, if it connects with a 
trap, and equal to the pressure in the return pipe, if 
it connects with a gravity apparatus. 

The steam which can be passed through a 2-inch 
pipe in an hour is capable of boiling about 4 tons of 
water, making allowance for loss of heat and friction, 
at a pressure of about 40 lbs. 

When a pan has two or more coils in it, they may 
take their steam from the same source, provided it is 
sufficient, but the returns from these coils should be 
separate ; with a separate trap to each return, and the 
discharge from these traps should not be put into the 



176 STEAM HEATING FOR BUILDINGS. 

same pipe, or into any confined space, where the dis- 
charging of one of the traps may cause pressure in the 
others, and cause them to discharge in advance of the 
proper moment. 

Long, flat wooden yats, with any convenient-shaped 
coil in the bottom, are often used for the evaporation of 
the water from brine by the salt manufacturer. Ex- 
haust steam from neighboring engines can be used 
here to advantage, thus utilizing heat that would other- 
wise be lost. 

146. Another common way of warming or boiling water, 
when the object is not evaporation, but the warming of 
a tank of water for laundry purposes, or when the 
addition of the condensed steam is a benefit (provided it 
is not greasy), is to put the steam-pipe directly into the 
water, in the form of an open butt, or a perforated coil. 

This mode is usually attended with noise, but it is 
quick and effective. 

When a perforated coil is used, it is usual for the 
fitter to have as many small holes in the coil as will 
aggregate equal to the area of cross-section of the pipe in 
the coil ; but in practice this is not nearly sufficient, if he 
wants to pass out all, or nearly all, of the steam and 
water which the supply-pipe is capable of passing. 

"Within an empty pipe, steam has a very high velocity, 
but striking the water, as it passes the holes, retards it 
so much that 5 to 10 times the area of the pipe in small 
holes has not been found too great in practice, the time 
of boiling lessening rapidly up to 10 times with shallow 
water and 40 lbs. of steam. 

The pressure of the steam and the depth of the water 
affects the time of heating; high pressure accelerates 
and deep water retards. 



BOILING AND COOKING BY STEAM. 



Ill 



The lower the pressure of the steam that will pass 
out, as it strikes the water, the less the noise will be ; 
and a good way to avoid noise is to have a large diameter 
coil or pipe in the water, with a great many small holes 
in it, letting the high pressure steam expand into this 
perforated pipe through a " throttled " valve, until the de- 
sired low pressure is attained. 

Another way to prevent noise, is, to place a tin cylin- 
der, with wire-cloth ends, filled with shot, over the end 
of the steam-pipe, the pipe turned up into the cylinder, 
and the cylinder in a vertical position. (See Fig. 52.) 




-FvcfSZ 



147. Another way to warm water with steam is at the 
nozzle or cock where it is drawn. A very simple method 
is by mingling the steam and the water after they pass 
their respective cocks or valves (as shown at Fig. 53). 
There should be no cock or valve put in the bib, a', 
for closing it will either force the water or steam (which 
ever has the greatest pressure) into the other. There- 
fore it is necessary to have little resistance in the pipe 
after passing the valves. 

A very simple noiseless nozzle is shown in Fig. 54. It 
consists of an enlargement after passing the valves filled 
12 



178 



STEAM HEATING FOR BUILDINGS. 



with shot, with a strainer to prevent the shot from pass- 
ing out ; or it may be filled with clean gravel, or anything 
the steam and water will have the least action on. By 
the regulation of the valves, a steady stream of water of 
almost any temperature between 212° and the tempera- 
ture of the cold water can be had. 





148. Often the pipe-fitter is called upon to construct 
means to warm water for bath-houses, laundries, or any 
place where they have no steam, and require no power, 
hence do not wish to have a steam boiler ; nevertheless 
use more water than can be warmed by the ordinary 
water back in the stove. The problem is, then, to warm 
the largest amount of water with the smallest expenditure 
of fuel. Fig. 55 shows an apparatus that for permanency 
and cost of maintenance is very satisfactory. A, is a 
tank of any convenient shape ; B, a cast or wrought 
iron boiler, similar to that used for green-house heating ; 
(7, connection from top of boiler to the side of the tank, 
not very high up, as all the water below the point it enters 
the tank cannot be estimated as part of the working 
capacity of the tank, for it is necessary to always keep 
this pipe covered with the water ; D, the return-pipe 



BOILING AND COOKING BY STEAM. 



179 



from the tank to the boiler, its inner end being 
carried a few inches above the bottom of the tank, to 
prevent sediment from being carried into the boiler, 
and E, the pipe leading from the tank, for the distribu- 
tion of the hot water, the position it occupies being im- 
portant, as it must always be above the pipe C, to 




prevent the possibility of drawing the water in the tank 
entirely down to that point. 

The tank may be furnished with a ball-cock, to the 
cold-water pipe, as shown at F, to keep a constant level 
of water. 

By feeding the water into the tank, instead of the 
boiler, impurities are deposited in the bottom of it, 
instead of being carried into the boiler. The same 
is true of all hot-water apparatus, if the bottom of 
the tank is below the return-pipe, with capacity enough 
in the tank to prevent rapid currents. 

A coil of pipe is sometimes used in a stove instead of 
a boiler, but it soon fills with mud or lime, and burns 
out. 



CHAPTEE XXII. 

DRY1NQ BY STEAM. 

149. Three-fourths of all tlie manufacturers outside 
of the metal trades, and even many of them, use heat 
for drying purposes ; and various as are the manufac- 
turers, so various are the modes of drying, in many 
instances satisfactory results being attained only by 
years of experience. 

No manufacturer of wooden articles can get along 
without a drying kiln. The laundry man or woman, 
the dyer, the hatter, the tobacconist, the piano and 
organ maker, the dried-fruit manufacturer, the japanner, 
the tanner, all must have a means of drying faster and 
more conveniently than can be had by exposure out-of- 
doors. 

Usually steam is used in drying rooms and drying 
kilns because of its cleanliness, its even distribution, 
its safety from fire, its easy and quick management, 
and the cheapness of its maintenance. 

The higher the temperature of a drying room, the 
cheaper can the articles be dried. This may not appear 
plain at first to those who have studied the laws of 
equivalents, but nevertheless it is so, being caused 
by local conditions, which always prevent the utiliza- 

180 



DRYING BY STEAM. 



181 



tion of all the heat. Thus, the greater the difference in 

temperature and 

the slower the 

movement of the air 

compatible with the 

amount of moisture 

to be carried off, the 

better the result in 

the laundry or dry 

kiln, or any place 

where rapid drying 

only is the object. 

In no other place 
is the power of ra- 
diant heat (direct 
radiation) more 
manifest than in 
the drying room, 
and more failures 
can be traced to 
placing coils under 
skeleton floors, or 
flat on the floor, 
than any other 
cause, except, per- 
haps, an ignorance 
of the principles of 
piping, which so 
many consider can 
be done by any one 
who wears a pair of 
greasy overalls. 

The writer has proved, in many cases, that the same 




182 



STEAM HEATING FOR BUILDINGS. 



amount of pipe or plate surface, distributed around 
and between the materials to be dried, will do the work 
in half the time it takes the heated air from an indirect 
coil. This is no mistake ; and further, wooden blocks 
can be dried lighter (proving there is more water 
driven off) by direct radiation than by indirect radia- 
tion, the times and temperatures being the same. 

According to the above it is plain, that in the con- 
struction of drying houses, for most purposes, the heat- 
ing surfaces should be so placed and distributed that 
the direct heat rays from the iron could fall uninter- 
rupted, on the greatest surface possible, of the materials 
to be dried. 

150. Fig. 56 shows a perspective of a good arrange- 
ment of a direct radiation laundry drying room coil, 




q.5Z 



utilizing all the radiant heat that is thrown off, and 
giving a thoroughly uniform heat throughout the room. 
A A are headers (often called manifolds), usually made 
of extra heavy pipe, to admit of tapping and threading, 
instead of using T's, for the cost of the heavy pipe and 
the drilling and tapping is very much less, as well as 
better and straighter, than a header composed of many 



DRYING BY STEAM. 183 

short pieces of large pipe and the necessary T's. 
(These remarks apply to all large coils.) 

B B are the spring pieces, threaded right and left 
handed ; C C, the leaves or sections of the coil ; and 
D B, the coil stands. The stands are always in pairs, 
to admit of giving the necessary division and inclina- 
tion to the pipes, and when viewed through the holes 
look like Fig. 57. The dotted lines are the centers of 
imaginary pipes to show the pitch. When coils are 
very wide in the direction of the length of the headers 
it is well to keep the coil stand 2 or 3 feet from the 
header at that end, to prevent the expansion from pull- 
ing the screws from the floor. 

The distance between the holes in the standing coil 
header is usually about 12 inches, or as wide as the 
clothes-horses are from center to center. 

The usual way to build these coils is to start at the 
bottom header, A', Fig. 56, and to put each leaf, C, to- 
gether continuously, working upward until you reach 
the elbow, E ; when all the leaves are so far con- 
structed, with all the elbows looking up, with their 
left-handed thread uppermost, count in and mark the 
right and left handed spring-pieces, B, then apply the 
upper header, A, and screw the whole up as nearly 
alike as possible. 

Do not be persuaded to do away witht he spring- 
pieces and the elbows through economy, so as to con- 
nect the upper headers straight, as in a box coil ; if 
you do you will have trouble should you want to take 
down a single leaf for repairs. 

Fig. 58 shows sectional perspective view through a 
laundry drying room : a being the coil ; b, the clothes- 
horse; c, the suspended rail, from which the horses 



184: STEAM BEATING FOR BUILDINGS. 

hang ; d, fresh-air inlet duct ; e, its damper or regulator ; 




/, ventilator with regulator, usually governed by a cord 



DRYING BY STEAM. 185 

and bell crank, and drawn back by a spring ; and g, the 
space into which the horses are drawn, which of neces- 
sity must be as long as the horses. 

This style of drying room gives the direct radiation 
from both sides of the leaf of the coil to the fabrics to 
be dried, and also exposes both sides of a fabric to the 
direct radiation of a section or leaf. 

For high pressure steam 1-inch pipe is generally 
used in the coil ; but if exhaust steam is to be used the 
pipes should be not smaller than l£ inch, and the 
total length of any one leaf should not exceed 40 feet 
under a back pressure of 2 pounds at the engine. 

For exhaust steam the upper header should be large, 
3 inches for 12 leaves of 40 feet each, or about 500 feet 
in the coil gives satisfactory results ; this should be 
increased in proportion to the increase in leaves, a 
4-inch pipe header being enough for a coil of from 900 
to 1,000 feet, composed of leaves of 40 feet each. 

Unless the exhaust steam is carried a long distance 
horizontally, 50 feet or more, the pipe leading to the 
header may. be one or two sizes smaller than the 
header, provided it is large enough for the engine. 

With steam of high tension, small pipe headers with 
T fitings may be used; but where the pressure is 
variable, a large header insures an equal distribution 
of steam to all the leaves. 

Sometimes gridiron or floor coils are used on account 
of saving expense, but the same amount of pipe in this 
form will not dry clothes as fast as the standing section coil. 

Figs. 59 and 60 show gridiron coils of easy construc- 
tion, a a being the manifolds or headers; b b, right and 
left elbows ; c c, coil pipes right handed ; and d d, right 
and left handed spring-pieces. 



186 



STEAM HEATING FOR BUILDINGS. 



In Fig. 59 the pitch of the pipes and headers is in 
the direction of the arrows. 

151. These coils are often used in lumber-drying 



&'?. $& 







kilns, but the same amount of pipe arranged around the 
walls in miter or wall coils will give a far better result, 
and will not be a receptacle for dirt, as a floor coil is, 



DRYING BY STEAM. 187 

requiring a skeleton floor over it, to walk on and pile 
the lumber on. 

In large drying kilns, on the direct radiation princi- 
ple, where pipe enough cannot be put on the walls, and 
for the better distribution of the heat, rows of stanch- 
eons should be put up to hang the coils on, in such a 
manner as not to interfere with the gangways. 

The tobacconist prefers to dry without artificial heat, 
in a temperature of about 60°, with a rapid change of 
air through the windows. This appears to give dry- 
ness without brittleness, but at night and in damp 
weather they must close the windows, and to get their 
stock out in time recourse must be had to steam coils. 

In experimenting for a well-known tobacco manufac- 
turer in fine cut, it was found that radiators or box 
coils placed in the middle of the rooms gave the best 
result. Wall coils under the windows made the room 
warm, but did not dry quickly, and the tobacco felt wet 
when brought into a cold room and allowed to remain 
for a short time. A strong ventilation with a tempera- 
ture of 80° made it too crisp ; but the box coils placed 
in the middle of the room, with a temperature of 65°, 
with a small ventilation, and the currents of air in the 
room, up at the center and down at the windows (con- 
trary to the general principle of warming for comfort), 
gave a result which was declared satisfactory. 

In piano-case manufactories, and where specialties 
in glued and veneered furniture of the best quality are 
made, the workmen are generally supplied with a dry- 
ing cabinet, of a size suitable to the pieces to be dried, 
in which the work is heated before the glue is applied, 
and into which it is again placed to dry properly. 

These cabinets are usually rectangular boxes, with 



188 STEAM HEATING FOR BUILDINGS. 

holes in the bottom and top, to allow the air from the 
room to circulate through them so as to carry off the 
moisture. Their steam coils are usually of the grid- 
iron pattern, flat on the bottom of the box, and with 
the valves on the outside. Sometimes they are heated 
indirectly by the warmed air conveyed in tin pipes 
from a large coil placed in some favorable position. 

Some manufacturers claim the quicker the work can 
be dried after gluing the better it will be. 

It is not profitable to dry by forcing air, as with a 
fan or blower, in connection with a steam coil. 

High-pressure steam should be used in connection 
with a blower. 

A temperature of 130° is considered ample, and can 
be easily attained in a drying room. 

The additional quantity of pipe necessary to raise 
the temperature of a drying room from 120° to 130°, if 
again added, will not raise it from 130° to 140°. 



CHAPTEK XXIII. 

STEAM-TRAPS. 

A steam-tkap is an appliance attached to certain 
classes of steam apparatus, whose object is to remove 
the water of condensation without a waste of steam. 

A gravity apparatus does not require a steam-trap of 
any kind; and the proof of a perfect gravity circulation 
is shown by the proper working of the apparatus with- 
out one. 

Traps may be separated into two principal classes — 
namely, traps which open to the atmosphere, or atmos- 
pheric traps, and direct return traps, returning the 
water to the boiler, without great loss of heat or any 
loss of water. 

Expansion systems of piping and heating require a 
steam-trap of some kind. When the water is to be 
saved, and returned to the boiler, the direct return trap 
is best. When the water is to be wasted, the atmos- 
pheric trap, which allows the water to cool to the lowest 
temperature is the best. 

Cooking apparatus, such as meat kettles, or kettles 
or tanks with coils in them, which condense much steam 
in a short time, should not be connected with a low- 
pressure gravity apparatus ; but should have a separate 

1*9 



190 STEAM HEATING FOR BUILDINGS. 

pipe from the boiler, and be connected to a trap, in 
consequence of the great and sudden shrinkage of 
steam, which takes place when they are quickly filled 
with cold water. They may be connected with a high- 
pressure gravity apparatus when the supply-pipes are 
very large. 

An intended gravity apparatus, which proves too 
small in the mains, or not properly done, so part of the 
piping remains full of water, can often be made to 
answer by the use of a direct return steam-trap ; but it 
should only be used when it is actually necessary. 

Atmospheric steam-traps should not be attached to a 
gravity apparatus under any circumstances, as they 
make an opening which permits the escape of water. 

CONSTEUCTION AND OPERATION OF THE DIRECT RETURN 
STEAM-TRAP. 

These traps have come into use within ten years, and 
form a new departure in steam-traps. They must be 
automatic in action, and of simple construction, and 
positive ; for an interruption of an hour or two, will fill 
the coils and pipes with water, and in very cold weather 
may be the cause of freezing ; so judgment must be ex- 
ercised in the selection of them. There are now two or 
three very good modifications of this trap before the 
public ; accomplishing all a steam-pump will do, in the 
way of returning water to the boiler, and with less loss 
of heat. 

Manufacturers of these traps may claim they should 
be used on gravity apparatus, for certain purposes — such 
as to regulate the heat to the weather ; but it is evident 
to a thoughtful man that an apparatus which is perfect, 



STEAM-TRAPS. 191 

and that will run for a life-time without interruption (if 
water is kept in the boiler and fire under it), or assis- 
tance from mechanical means, should not be put to the 
chance of an occasional interruption by the use of a 
nicely adjusted machine which wears out. 

These traps are excellent in their right place, being 
capable of returning the condensed water from coils 
into the boiler, no matter where the coils are placed ; thus 
doing away with tanks and pumps, in expansion appara- 
tus, and thereby saving heat. Also when a building has 
no basement, or when the boiler cannot be placed low 
enough for all the water to return by gravity, they can 
be used on the low coils ; but in a case where the build- 
ing is high, it would be best to heat the upper floors 
by a separate gravity system, and the lower floor or 
basement by a pipe of its own ; so that if there was an 
interruption, the low coils only would be affected, and 
thus give less for the trap to do. 

The principle involved in these traps is simple, being 
alternately a vacuum and a pressure ; but, like the single 
acting reciprocating pump which has no fly-wheel to 
help it at the end of the stroke, it must have some kind 
of an auxiliary. 

With the aid of the diagram, Fig 61, the action of 
these traps may be explained. "A represents the trap 
proper ; C, the receiver, which holds a certain quantity 
of the return-water ; D, a steam-pipe from the boiler to 
the trap ; E, a pipe from the trap to below the water- 
line in the boiler ; and F, a pipe from the receiver to the 
trap carried up inside the globe. It will also be seen, 
these pipes are provided with valves ; the steam-pipe 
has a globe-valve, and the other two pipes, check- 
valves; the valve in the pipe F, opening toward the 



192 



STEAM HEATING FOR BUILDINGS. 



trap, and the valve in the pipe E, opening toward the 
boiler. 

Now, if the valve in the steam-pipe is opened and 
steam admitted to the globe (i>), until all the air is ex- 
pelled, and the steam allowed to condense, as it will do 
in a short time after the valve is closed (by the loss 
of heat from the steam through the sides of the globe 




to the outside atmosphere), there will be a vacuum 
formed in the globe, more or less perfect, which will 
draw water from the receiver (G), when there is a press- 
ure in the pipe which comes from the coils, or else- 



STEA31-TRAPS. 193 

where, and this water, passing the check- valve in F, will 
overflow into B, and cannot return to C, for two reasons 
—because it cannot pass the check-valve backward and 
cannot get back over the top of the pipe F. Now, if the 
valve in the steam-pipe is opened, and the pressure of 
the boiler admitted into the top of the globe (B), the 
pressure will become equalized between the boiler and 
the globe, and allow the water to pass down the pipe 
(F), and into the boiler of its own gravity (precisely as 
it would if everything was opened to atmosphere), going 
through the other check-valve, which will not allow it 
to pass back again, when the valve in the steam-pipe is 
closed, and condensation will again form a vacuum ; 
which will once more draw the water from the receiver, 
to flow down into the boiler, when the steam-valve is 
again opened, and thus the action goes on, being simply 
that of a pump without a piston. 

This principle was understood and used, substantially 
as explained above, before the automatic traps were 
introduced; but as it was necessary to construct the 
two globes, or tanks, of large size, to avoid too frequent 
attendance ; and as it required manipulation, at irregu- 
lar intervals, which, if neglected, would fill the pipes 
with water, it was not much used. Now, since automatic 
contrivances have been invented, which takes the place 
of manipulation, and which can be depended on with some 
degree of certainty, these traps can be, and are, used on 
apparatus which otherwise would be almost useless. 
Thus the difficulty to be overcome in this class of traps 
as before mentioned, is to construct an automatic con- 
trivance for opening and closing the steam- valve which 
can be relied on. 

Fig. 62 shows one of these traps, which has been 
13 



194 



STEAM HEATING FOR BUILDINGS. 



selected as an example, not because the trap is con- 
sidered the best — for there are others equally good — but 
because the action of the auxiliary is so easily explained. 
It is a view of the trap when set up ; H is the steam- 
pipe ; G, the pipe from the receiver to the trap ; and F, 
the pipe from the trap to the boiler. The valve marked 
D is the steam- valve, which is automatically regulated, 




and is a rotary slide-valve ; E, a connecting rod, be- 
tween a crank on the valve stem, and an arm, with slack 
motion, and a part of the casting C, which rocks on a 
stud ; C, a track, on which rolls a ball, also a part of the 
casting, which rocks on the stud before mentioned, and 
which engages another stud, on the lever B ; the lever 



STEAM-TRAPS. 195 

B and its weight are a counterpoise to a float inside 
the globe. The action is as follows : when there has 
been a vacuum in the globe, the water will pass 
through the pipe G, and fill the trap, consequently it 
raises the float and lowers the lever and counter- 
poise, whose stud engaging C, draws it down, until the 
track passes the horizontal position, without affecting 
the connecting rod E, on account of the lost motion, 
until the track has passed the horizontal position, then 
the ball will roll along the track, and strike on the 
opposite end against the hook — a blow sufficient to 
move the valve on its seat, and open it to its full 
extent ; but not before the globe is full of water. The 
reverse motion is similar : the float lowering, but not 
affecting the valve, until the water is nearly all out of 
the globe ; the slack motion allowing the valve to 
remain open, until the track again passes the hoizontal 
position, when the force exerted by the blow on the 
hook at the other end of the track closes the valve 
suddenly. 

Among the atmospheric traps are found the old ex- 
pansion traps, now little used ; and the open float-traps, 
which still form a necessary part of certain apparatus. 

Fig. 63 shows a well known form of open float-traps, 
used both in this country and in England, of which there 
are many modifications of minor importance ; the action 
and principle remaining the same. A is a cast-iron pot, 
sufficiently strong to withstand high-pressure steam, with 
an inlet at F; B is another pot fan open pot), inside 
the pot A, with a spike at the center of the bottom, and 
a guide to keep the inner pot in a central position. C 
is a brass tube screwed into the cover Z), and forming 
a valve with a spike at the inside of the bottom of the 



196 



STEAM HEATING FOR BUILDINGS. 



pot B; E is a valve in the cover of pot A, which, when 
opened, acts as an air- valve, or bloio-throiigh, to hurry up 
the circulation when first heating up the coils. 

The pot-trap operates thus : the condensed water 
from the coils, etc., runs in at the pipe F, and fills the 
outer pot A with water, until it floats the inner pot B, 
against the stem C, closing the valve formed by the 




spike and the tube, thus closing the outlet to the tank or 
sewer. The water, which still continues to flow into the 
outside pot, rises, and overflows into the inside pot. 
Then the latter sinks, and opens the valve which the 
spike forms with the hollow stem, and allows all the water 
in the inner pot to be forced up through the stem and 
out by the pressure of the steam in the upper part of 
the pot acting on the surface of the water. Thus, when 
the inner pot becomes bouyant again, by the discharge 
of its water, it closes the valve, and leaves it so, until 
the increase of the condensed water again overflows it. 
This action is intermittent, the frequency of it depending 
on the amount of work to be done. 



STEAM-TRAPS. 197 

There is one point in the construction of this trap on 
which its working depends — namely, the area in square 
inches of the hole in the end of the hollow stem C must 
be no larger than the quotient obtained from dividing 
the weight in pounds of the inner pot when submerged, 
by the maximum pressure in pounds per square inch of 
the steam to be carried. 

Thus, if the inner pot weighs 12\ pounds under water, 
and the greater pressure of the steam is to be 100 pounds 
per square inch, the hole must be a little smaller than J 
the area of a square inch, say a round hole J of an inch 
in diameter, which leaves a factor of safety of \ the 
weight of the pot. The reason for this is plain, when 
we consider that there is practically no pressure within 
the stem when the valve is closed ; and for the pot to 
sink, when it is full, it must be heavy enough to pull it- 
self away from the stem, and still be light enough to float 
J of its weight when empty. 

This type of trap possesses a special point of excellence 
— it will discharge the water of condensation from coils, 
or from the cylinder of an engine, into a tank or sewer, 
at a very much higher level than that which it drains, 
and it will keep them as dry as if it discharged down- 
ward. It is the only trap opening to atmosphere ivhicli will 
do this, except by blowing through continuously. 

It is peculiarly adapted to elevator engines, which stop 
and start frequently, and are operated from the car or 
an upper floor, as it removes the water at a high tem- 
perature, and will keep a steam-chest dry by removing the 
water which accumulates while the engine is standing 
with steam turned on ; which engines thus used require 
that they may be always ready for a call. 

There is another open float-trap, Fig. 64, which contains 



198 



STEAM HEATING FOR BUILDINGS. 



a special point of merit, the value of which is not yet 
generally understood, — namely, a trap capable of taking 
recognition, so to speak, of temperature, as well as 
quantity, and which will discharge its water down to 




atmospheric temperature and pressure, no matter what 
may be the temperature of the water in the coils due to 
high pressure. 

To make this clear, it is necessary to explain, that 
water which falls to the bottom side of a nearly horizon- 
tal pipe, with 50 pounds pressure of steam in it, has not 
fallen to a temperature of 212° Fahrenheit, as is very 
generally supposed, but has simply parted with the 
latent heat of the steam, incidental to the pressure, leav- 
ing the temperature of the water (when the flow and press- 
ure of the steam are maintained) a very little less than 
the temperature of the steam. This water will again 
give off some of its sensible heat, to be again made 
latent, making steam of a lower pressure when allowed 
to expand. But it must not be understood that all the 
water flies into steam. It does not — the quantity of 
water converted into steam being represented by the 
ratio the latent heat of the steam, at the different press- 



STEA3I-TRAPS. 199 

ures, bears to the sum of the latent heat and the sensi- 
ble heat of steam. 

Thus, when water is drawn directly from a high-press- 
ure coil into the receiver of a trap, and is discharged 
against atmosphere, before the water has cooled below 
212°, it is attended with considerable loss of heat. This 
can be seen in the blowing of a gauge-cock, for, though 
the water is solid and dense in the boiler, when it is 
drawn some of it flies into steam, and makes a cloud 
which often deludes the novice into the belief that it is 
all steam, and that possibly he has low water. 

The construction of this trap is plain : it consists of 
an outside case with a loose cover, an open float with 
the mouth down, and a common plug-cock operated by 
the float. 

When steam or water above 212° in temperature is 
discharged through the cock, and under the float, the 
latter is immediately raised by the pressure of the 
vapor underneath and between the float, and the water 
which cannot flow over the case. This action closes 
the cock, which will remain closed until the vapor 
condenses and allows the float to once more sink, when 
the cock again discharges the hot water behind it. If 
this water is below 212°, it will pass rapidly out of the 
case under the edge of the float; but when it again 
becomes hot enough to make a little steam, the float 
raises, and the cock is again shut. 

This trap cannot be used on an engine, as it will not 
discharge any considerable quantity of water until the 
temperature is below 212° ; but for an expansion sys- 
tem, or for exhaust, it would be a good one. 



CHAPTEK XXIV. 

BOILER CONNECTIONS AND ATTACHMENTS. 

157. Feed- Pipes. — The feed- valve should be a globe 
or angle valve placed near the boiler, with the fewest 
possible joints in the feed-pipe between it and the 
boiler. If it is a loose or swivel disk valve, it should 
be secured with solder (sweated in) in the threads of 
the double part of the disk, so as to make it almost 
impossible to loose the disk from the stem ; a mark with 
a center punch or chisel is not enough. The valve 
should be so turned toward the boiler that the inflow- 
ing water will be under and against the disk, so that, in 
the case of the loss of the disk, it will not act as a 
check-valve against the influx of the feed-water. This 
arrangement will bring the pressure of the water in the 
boiler always against the stufling-box of the valve ; but, 
all things considered, it is best. 

The check-valve should be close to and outside the 
feed- valve, with only a nipple between them. Always 
use horizontal check-valves, as they admit of easy 
cleaning. With the ordinary vertical check it is neces- 
sary to take down some part of the feed-pipe to clean 
it. 

When two or more boilers are fed from the same 

200 



BOILER CONNECTIONS AND ATTACHMENTS. 201 

pump, or when the pump is used for pumping water 
for some other purpose, it is well to have a stop-valve 
on each side of the check- valve, as it will enable the 
engineer to get at his check without stopping the 
water elsewhere. 

In passing through boiler walls or cast-iron fronts, 
care should be taken that the feed-pipe does not nest, 
or the settling of the boiler will break it off. 

Use a flange union on the feed-pipe instead of the 
common swivel union ; the engineer can take it apart 
with a monkey wrench, and it makes a more permanent 
job, and it will not leak. 

Never put a T in the feed-pipe inside the feed- valve 
for the purpose of a blow-off; but make a separate 
connection to the boiler. 

Blow-off Cocks. — Never use anything but a plug cock 
of the best steam metal throughout. The reasons for 
using a cock are, that the engineer is always sure when 
he looks at it whether it is shut or open ; it gives a 
straight opening; if chips, packing, or dirt gets into 
the cock it will shear them off when closing, or if it 
does not, the engineer knows it is not shut. Do not 
use an iron-body cock with brass plug, for when the 
cock is opened to blow down a little, the hot water 
expands the plug of the cock more than the body, and 
it is almost impossible to close it. Do not use a globe 
or angle-valve, as you cannot always tell when it is 
shut ; a chip or dirt getting between the disk and seat 
will prevent its closing. I have seen two fine boilers 
destroyed from this cause. Gate or straight-way valves 
are subject to the same objections as globe or angle. 

When it is practicable there should be a T with a 
plug in it in the blow-off pipe outside the bloAv-off 



202 STEAM HEATING FOB BUILDINGS. 

cock, the plug arranged so as to be removed when the 
cock is closed. By this means the engineer can always 
tell if he is losing water from his boiler. 

The blow-off pipe should be large, with few bends in 
it, and fire bends are better than elbows. It should be 
attached to the bottom of the shell of a horizontal 
boiler, and not tapped into the head a few inches up. 
When there is a mud-pipe, attach it at the opposite 
end from the feed-pipe. 

Safety -Valves, — They are the main-stay of the en- 
gineer, acting both as a relief and a warning signal. 
They should be attached to the steam-dome high up. 
At the side is better than the top, as they are not so 
liable to draw water when blowing off in that position. 
They should be large, and have a large pipe connection 
all to themselves. The ordinary cross-body safety- 
valve is very much to be condemned, and I think in 
some countries there are regulations against their use. 
They are constructed to save making an extra connec- 
tion for the main steam-pipe, thereby drawing the 
largest amount of steam directly from under the disk 
of the safety-valve. A weighted safety-valve is better 
than a spring- valve when it can be used, as the lifting 
of the valve makes practically no difference in the 
leverage ; not so with a spring- valve, for the higher it 
is lifted the more power it takes to compress the 
spring. 

Gauge or Try Cocks. — Gauge-cocks are various in 
style, the wood handle compression gauge-cock is a 
very good kind for all purposes. "When setting gauge- 
cocks care should be taken that they are not too low, 
and that the drip will not flow over the person who 
tries them. They should be tapped directly into the 



BOILER CONNECTIONS AND ATTACHMENTS. 203 

boiler if possible ; but when it is necessary to use a 
piece of pipe to bring them through a boiler front or 
brick-work, give the pipe an inclination backward, that 
the condensation may run back and into the boiler. 
When the pipe inclines outward and down, the con- 
densation remains in it and the cock, and will deceive 
the unwary, giving the appearance of plenty of water 
with a short blow. 

Glass Water- Gauges. — "Water-gauges are best set 
when attached to a vertical cylinder at the front of the 
boiler. The cylinder should be connected to the boiler 
with not less than 1-inch pipe, top and bottom ; the 
top or steam connection should be taken from the 
boiler shell near the front head, and not from the dome 
or steam-pipe, as the draught of steam in either will 
cause the glass to show more water than the boiler 
contains. The bottom or water connection should be 
taken from the front head at a point where about two 
thirds of the water in the boiler will be above it and 
one third below ; this will lessen the chances of the 
pipe stopping up with mud, etc., and it should also be 
provided with a half-inch pipe at the lowest point for 
a blow-out. W T hen gauge glasses are set this way the 
condensation in the cylinder is downward, and the flow 
of water being toward the boiler through the bottom 
pipe, the tendency is to cleanse the glass and cylinder 
and keep them so. 

Steam- Gauges should never be set much above or 
below the boilers to which they are attached, as each 
two feet of fall or elevation from the direct connection 
is nearly equal to a difference of one pound on the 
steam-gauge ; it is always so when the gauge is below, 
for the condensation in the gauge-pipe fills it with water, 



204 STEAM HEATING FOR BUILDINGS. 

wliicli leaves a pressure on the steam-gauge equal to 
the hydrostatic head, which is a little over two feet per- 
pendicularly to the pound per steam-gauge, giving the 
gauge the appearance of being weak. When the gauge 
is above it is not so always, though generally so even 
then, for the pipes being long and of small diameter or 
trapped, which prevents a circulation of steam in them, 
they fill with water, which acts against the pressure 
from the boiler and gives a gauge the appearance of 
being strong. It is a good plan to connect the gauge- 
pipe to a boiler below the water-line, say 12 or 18 
inches, and have the gauge on the boiler about 12 
inches above the water-line, using no water-trap or 
siphon, that the water may run back from the gauge 
when there is no pressure in the boiler, and thereby 
prevent the possibility of freezing or of getting steam 
to the spring of the gauge. 

Sometimes a steam-fitter has to run a gauge pipe a 
long distance to an office or engine room. When such 
a gauge is far above the boiler he should run a large 
pipe direct from the steam-dome, and give it sufficient 
pitch to clear itself of water ; it should be covered with 
some non-conducting material, and be of such size that 
the flow of steam through the pipe to supply the loss 
by condensation will be so slow as not to interfere with 
the flow of water along the bottom of the pipe in a con- 
trary direction, and it should have a siphon imme- 
diately under the gauge. 

When it is necessary to have a gauge very much 
lower than a boiler, fill the pipe with water, but before 
doing so remove the glass and lift the hand or index 
over the stop-pin and mark where it remains station- 
ary ; now fill the pipe to its highest point with water, 



BOILER CONNECTIONS AND ATTACHMENTS. 205 

then draw the index from its spindle and set it back 
to the mark where it remained stationary before the 
pipe was filled, and press it on; then bring it to its 
normal position on the stop-pin and adjust the glass. 

The Main Steam-Pipe for Heating Apparatus should 
be high up on a boiler, and any pipe larger than 2 inch 
should not be tapped in, but connected with a flange 
bolted or riveted to the boiler. Two and a half inch 
pipe and larger sizes have eight threads to the inch, 
which forms too coarse a pitch to be tapped into one 
thickness of boiler iron. 

Automatic water-feeders, combination water-gauges, 
or steam-gauges, should not be tapped into the steam- 
heating or engine pipe, as the draught of the steam 
through the pipe interferes with their proper working. 

Engine or pump pipes should not be taken from the 
steam-heating pipe, as the draught they cause relieves 
the pressure in the heating apparatus and spoils the 
circulation, especially if it is a direct return gravity 
circulation. 

"With an automatic return steam-trap, applied to an 
old job, if the steam-heating pipe is large enough, it 
will not be necessary to remove the engine pipe, but 
should the circulation be still defective, remove the 
engine pipe to the shell of the boiler, and remote from 
the heating pipe. 



CHAPTEE XXV. 

MISCELLANEOUS ARTICLES. 
CUTTING WALLS AND COVERING RISERS. 

158. Architects often omit to leave a recess where 
required in the walls of a building, and the fitter has to 
cut one. 

In his anxiety to put up as much pipe as possible, 
and as he considers the cutting of the wall does not 
properly belong to him, he cuts it in the quickest and 
easiest manner he can, regardless of the appearance, 
and in some loosely put up walls it is a difficult task to 
make an attractive or even satisfactory piece of work. 
The proper way would be to have the openings left and 
cutting avoided ; but if it must be done, it should be 
well done. 

Let the fitter provide himself with sharp chisels, and 
a light hammer, and he can generally cut a brick, with- 
out disturbing it in the wall ; but it is also necessary 
for the master mechanic to consider wall cutting labor, 
and to give the workman to understand he will be 
credited with cutting walls as well as for putting up 
pipe. 

The fitter should get the architect's permission 
before he commences to cut, for otherwise there may 

206 



TURNING EXHAUST STEAM INTO CHIMNEYS. 207 

be much injury clone to a building, by having a recess 
cut from top to bottom, near a front wall or corner. 

The best way to cover a riser recess is with a board. 
Have the grounds put on before the plastering is done, 
and have the panel screwed on afterward. The panel 
may be fancy iron-work, with holes in it, which makes 
a very permanent method. A moveable panel admits 
of access to the pipes to make repairs without breaking 
the walls. 

Some architects require the recess to be plastered 
over, using slate, or coarse wire-cloth, to hold the 
plaster with, so as to entirely hide the appearance of a 
pipe, but even then they do not entirely succeed, for 
two or three reasons. "When a slate is stuck over the 
recess with plaster-of-Paris, and plastered over all, the 
expansion of the slate cracks the plaster; when plas- 
tered on wire-cloth, it does very well, and will not 
crack, but it will turn a dark color in time, as will any 
thin covering when it becomes warm ; and the con- 
tinuous current of air passing up the wall at that par- 
ticular spot deposits more dust there than at any other 
point, and leaves a well-defined mark. 

For the same reason, the walls back of radiators get 
darker more rapidly than the walls of any other part 
of the room. The same is true of curtains which hang 
near a register. In parts of the country where soft 
coal is generally used this is very apparent. 

TURNING EXHAUST STEAM OR VAPOR INTO CHIMNEYS. 

159. There is a custom among steam-fitters, and 
others, of turning the exhaust steam from an engine 
into the boiler chimney in buildings, ostensibly to 



208 STEAM HEATING FOR BUILDINGS. 

make the draft better, but in reality to save running an 
exhaust pipe to the roof of the building. 

Exhaust steam, turned into a long or high brick 
chimney, will not improve the draft, but impair it. 

In locomotives the exhaust steam is turned into the 
stack to increase the draft, and in short iron stacks of 
portable engines it has the same effect, when properly 
put in ; but it must be borne in mind, that to be effect- 
ive, it must have such proportions as to make it an 
injector, to increase the velocity of the air by contact 
with its own high velocity, before it has time to expand 
and fill the stack. 

In long iron stacks, a little steam turned into them 
may be of some use in warming the stack (which cools 
rapidly from contact with the wind and air in cold 
weather), and by assisting the upward current of smoke 
or air, by mixing with it. Under certain conditions, it 
makes a mixture of steam and air lighter than the air 
alone, while, if the increased velocity caused thereby 
more than compensates for the extra volume which has 
to pass it, may be an improvement. 

But usually the exhaust steam chokes a very long 
chimney, the latent heat of the steam passing through 
the sides of the chimney (especially an iron one), and 
leaving the condensation to run down the insides of the 
chimney in streams, and to be again partly re-evapor- 
ated by absorbing heat from the gases of combustion. 

In brick chimneys this is very apparent, condensing 
and soaking into the brick-work, and absorbing as much 
heat from the gases of combustion to evaporate and 
drive off a cubic foot of it as would cool 30,000 cubic 
feet of air 100 degrees Fahrenheit. It also destroys 
the chimney. 



SOLDERING OF PIPES AND BRASS FITTINGS. 209 



SOLDERING OF PIPES AND BRASS FITTINGS. 

160. Often it is necessary to solder or " sweat " pipes 
into fittings, or male and female threads of brass work. 
The latter is no trouble, and can be done by tinning the 
parts to be put together, using only resin for a flux, if 
done while new, and then screwing them together while 
hot. 

"When iron pipe has to be sweated into iron fittings, 
malleable iron fittings should be used, because they 
can be tinned by using muriatic acid reduced with 
zinc ; cast iron does not solder well. 

When about to sweat a pipe and fitting together, 
wipe the threads carefully, and run a carefully wiped 
die over the male thread, to entirely clean it, using a 
clean tap, to remove any oxide or grease from the 
female thread in the fitting, then tin cleanly, using 
muriatic acid for a flux, and screw them together while 
both are hot. 

There is no advantage in soldering a frost burst in 
an iron pipe, through which steam or very hot water 
passes, for it will not last. 

In iron water-pipe, rather than remove the pipe, it 
may be soldered, but it must be thoroughly cleaned 
and tinned, and a heavy wipe joint made on it ; bolting 
is of no avail. 

When cracks appear in brass or copper pipes, with- 
out any apparent cause, there is very little use in 
soldering, for they are usually caused by undue expan- 
sion or jarring, and are a fault of construction, which 
soft solder will remedy for a very short time. 

Parts of brass goods, such as valves, etc., which are 
14 



210 STEAM HEATING FOR BUILDINGS. 

liable to jar loose, should be sweated together in par- 
ticular places, such as the disk on a feed-valve, or main 
stop-valve. 

PAINTING PIPES. 

161. Distributing pipes may be painted with any- 
thing that will arrest oxidation; lead paints are very 
good, for they are the poorest conductors of heat ; but 
lead paints should not be used on radiating surfaces, 
as they lessen the radiating and transmitting power, 
many coats applied, year after year continually, im- 
pair their efficiency greatly. 

Zinc paint is considered somewhat better, but there 
is good reason to say it should not be used. 

Raw linseed-oil, with ochre of the required color, 
and turpentine, form a good preparation for radiators, 
when they are to be bronzed, as it gathers and " fixes " 
any machine oil or dirt there may be on the pipes, and 
will make a good bach for the bronze. 

Black baking japan, or black air-drying japan, are 
very good substances for painting radiators with, as 
they appear to impair their efficiency but little, and 
two coats will give a good gloss, which does not re- 
quire to be renewed; a wipe with a slightly oiled 
woolen cloth will give them a fresh appearance. 

Black paraffine varnish should not be used ; it is not 
permanent ; it cokes with heat, and has no body. 

Indirect coils, or coils or heaters which cannot be seen, 
it is best not to paint. 

Dust allowed to collect on heaters impairs them very 
much. 



CHAPTEE XXVI. 

MISCELLANEOUS NOTES AND TABLES. 

These notes and tables will be found of service in 
estimating. 

The avoirdupois pound is always to be used, unless 
otherwise specified. It contains 7,000 Troy grains ; the 
grain is always Troy. 



16 drams 


= 1 ounce. 


oz. 


16 ounces 


= 1 pound. 


lb. 


25 pounds 


= 1 quarter. 


qr. 


4 quarters 


= 1 hundred. 


cwt. 


20 cwt., 2,000 lbs. 


= 1 ton. 





The gross ton (in which the quarter becomes 28 lbs., 
the hundredweight, 112 lbs., and the ton, 2,240 lbs.) is 
used in estimating English goods at the U. S. Custom- 
House ; in freighting ; in the wholesale coal trade ; and 
in the wholesale iron and plaster trades, and when 
specified. 

1 lb. avoir. = 16 oz. avoir. = 7,000 grs. Troy. 
1 " " = 437.5 " " 

27 T V cubic inches of water weigh one pound avoir- 
dupois, at a temperature of 40°. 

211 



212 STEAM HEATING FOR BUILDINGS. 

A cubic foot of water, at a temperature of 60°, weighs 
999 ozs., and is taken as 1,000 ounces, or 62^ pounds, 
for all ordinary calculations. It weighs a little less 
than 60 pounds when the temperature is 212°. 

A cubic foot of water contains very nearly 7 J gallons, 
and for rough calculations may be taken as such 
(7.4805 gallons is actual) number. 

A cubic inch of water, at its greatest density, weighs 
252.693 grains ; a cubic foot, 58,372.0 grains. 





1 gal. = 231.0 cubic in. 


1 cub. ft., 


1\ " = 1728.0 


1 bushel, 1ft 


9 T 3 o " = 2150.42 


1 cord, 128.0 " 


a cc 


1 cub. yd., 27.0 " 


= 46656.0 


1 barrel,* 421 " 


31J " = 7276.5 



* A flour barrel will hold 33.28 gallons, or 4.449 cubic feet, or 2.79 
heaped bushels (called 2| bushels). 

In estimating quantities of water by barrels, 31^ standard gallons 
equals the barrel. 

TABLE NO. 9. 

WEIGHT OF A CUBIC INCH OF VARIOUS METALS. 



Iron, cast 0.263 of a pound. 

" wrought 0.28 

Lead 0.41 

Copper . 32 

Nickel 0.30 

Steel 0.28 

Tin 0.265 " 

Zinc, cast 0.24 

" rolled 0.26 

Brass, steam metal . 315 ' ' 

" yellow 0.282 



MISCELLANEOUS NOTES AND TABLES. 213 
TABLE NO. 10. 

WEIGHT OF A CUBIC FOOT OF VARIOUS BUILDING MATERIALS, IN POUNDS 
(APPROXIMATE). 

Granite 168.0 pounds 

Marble 165.0 " 

Sandstone 135.0 " 

Blue-stone 165.0 " 

Slate 180.0 " 

Mortar, dry 80.0 to 100 pounds. 

Common Brick 112.0 pounds. 

Dry Sand 100.0 " 

Fire-brick 135.0 " 

One perch of stone-work, in walls or foundations, 
measures 24§ cubic feet. 

One thousand common bricks, laid in a wall, makes 
about 50 cubic feet, varying a little for different bricks. 

Six fire-bricks to each square foot of lining, one 
brick thick, is sufficient ; 1,000 bricks will make 170 
superficial feet of lining, laid in the ordinary way. 

To find the weight of iron castings by computation. — 
Find its solid contents, in inches, and multiply them 
by .26, and it will give the weight, in pounds. For 
rough calculations, it will do to divide the cubic inches 
by 4, and call the answer pounds. 

To find the weight of any other casting, or forging. — 
Find its solid contents in cubic inches, and multiply by 
the weight of a cubic inch of the metal, as given in the 
table, "Weight of a cubic inch of various metals." 

For irregular castings, which are difficult to measure, 
and cannot be conveniently weighed, a rough estimate 
of their weight may be taken, provided they are not 
cored out, by weighing the pattern, if it is of soft pine, 
and allowing 13 times the weight of the pattern, if it 



214 



STEAM HEATING FOR BUILDINGS. 



is new, or just out of the sand, and 14 times if it has 
laid in the pattern loft for some time. 

A square foot of cast-iron, one inch thick, weighs 
37J pounds. To find what a square foot of any other 
thickness will weigh, multiply 37J by the thickness in 
inches, or fractions of an inch. 

A square foot of rolled wrought-iron, one inch thick, 
weighs 40 lbs. To find the weight of boiler plates, or 
sheet-iron, per square foot, multiply 40 by the decimal 
of an inch in thickness the required plates are to be. 

TABLE no. 11. 

THE FOLLOWING TABLE SHOWS THE DIFFERENCE BETWEEN AMERICAN AND 

ENGLISH WIRE GAUGES, AND THE THICKNESS OF PLATES, IN 

DECIMALS OF AN INCH FOR EACH. 



No. of Gauge. 


American. Inches. 


English. Inches. 


0000 


046 


0.454 


000 


0.4096 


0.425 


00 


0.3G48 


0.38 





0.3248 


0.34 


1 


0.2893 


0.3 


2 


0.2576 


0.284 


3 


0.2294 


0.259 


4 


0.2043 


0.238 


5 


0.1819 


0.22 


6 


0.1620 


0.203 


7 


0.1442 


0.18 


8 


0.1284 


0.165 


9 


0.1144 


0.148 


10 


0.1018 


0.134 


11 


0.0907 


0.12 


12 


0.0808 


0.109 


13 


0.0719 


0.095 


14 


0.0640 


0.083 


15 


0.057 


0.072 


16 


0.05 


0.065 


17 


0.045 


0.058 


18 


0.04 


0.049 


19 


0.035 


0.042 


20 


0.031 


0.035 



MISCELLANEOUS NOTES AND TABLES. 215 

To find the weight of a cast-iron pipe, for one foot of 
its length. — Multiply the diameter of the pipe in inches 
by 3.1416, and multiply the answer thus obtained, by 
the thickness of the pipe in inches, or decimals of an 
inch, then by 12 and 0.26 respectively ; or instead of the 
last two, use 3.15. 

This will give about the weight of the pipe, includ- 
ing the hubs, as the outside circumference of the pipe 
is not the mean length of the iron, according to its 
thickness. To be exact. Proceed as above, but take 
one thickness of the iron from the diameter of the pipe 
first, and it will give the weight of the pipe without 
hubs or flanges. 

Example. — Ee quired the weight of a 12-inch pipe, J 
inch thick, for one foot of its length. Thus : 12 in. — 0.5 
= 11.5 x 3.1416 = 36.127 x 0.5 = 18.063 x 3.15 = 56.89 
pounds. 

The 3.15 is the sum of 12 inches for the length, and 
0.263 for the weight. 

Definitions and computations in mensuration, re- 
quired by the steam-fitter. 

The perimeter of a figure is its outer boundary, with- 
out regard to shape. 

A true circle forms the shortest perimeter for the 
greatest area inclosed, and is called a circumference. 

A diameter is a right line, passing through the center 
of a circle. 

A diameter is very nearly jW of the circumference of 
the same circle, or, to be exact, 0.3183 of it. Kule. — Mul- 
tiply the circumference by 0.3183, and it will give the 
answer, in the same denomination. 

A circumference is 3 r W of the diameter of the same 
circle very nearly, or, to be exact, 3.1416. 



216 STEAM HEATING FOR BUILDINGS. 

The square of the diameter of a circle is multiplying 
it once by itself. Thus, if the diameter is 4, the square 
will be 16. (4 inches x 4 inches = 16 inches.) 

To find the area (the number of square inches) 
within a circle. — Multiply the square of the diameter 
by 0.7854, and it will give the answer in the same de- 
nomination as it was squared in. Thus, 4 " x 4 " = 16" 
X 0.7854 = 12.566 square inches, whose diameter is 4 
inches. 

The cube of a number is the number multiplied by 
itself twice. Thus, 4 x 4 = 16 x 4 = 64. 

When the cube of the diameter of a sphere is mul- 
tiplied by 0.5236, it gives the solid contents, in numbers 
of the same denomination as it was cubed in. Thus : 
4" x 4" = 16 " x 4"= 64" x 0.5236 = 33.51 cubic inches, for 
a ball 4 inches in diameter ; and when multiplied again 
by 0.263 it gives 8.813, which will be the weight in pounds 
of a cast-iron ball of the same diameter. 

A cylinder of the same length as its diameter has 
the same surface as a sphere of equal diameter. 

To find the surface of a cylinder 4 inches in dia- 
meter and 4 inches long. — Multiply the diameter by 
3.1416 and the product by the 4 inches in length. 
Thus, 4 x 3.1416 = 12.566 x 4 = 50.2656, the square 
inches on the outside of a 4 x 4 cylinder. 

To find the surface of a sphere, 4 inches in diameter. 
— Square the diameter, and multiply by 3.1416. Thus : 
4x4 = 16x3.1416 = 50.2656. 

To find the outside surface of a pipe. — Multiply the 
outside diameter by 3.1416, and by the length in inches, 
and divide by 144, it will give the answer in square feet. 

To find the pressure, per square inch, a column of 



MISCELLANEOUS NOTES AND TABLES. 



217 



water of any height will exert. — Multiply the height of 
the column, in feet, by the weight of a cubic foot of 
water in pounds at the temperature the water may be, 
and divide by 144. 

Example. — Required the pressure, per square inch, of 
a head of water of 200 feet, and when the temperature 
of the water is 40° Fahr. (weight 62.} pounds). Thus, 
200 x 62.5 = 12500^144 = 86.8 pounds per square inch. 

Required the pressure of the water at a temperature 
of 212°. Thus, 200 x 59.80 = 1196 + 144=83.05 pounds 
per square inch. 

TABLE NO 12. 



THE FOLLOWING TABLE OF DIAMETERS, CIRCUMFERENCES, 
IS GIVEN FOR "READY-RECKONING." 



AND AREA9 



Diameter. 


Circumfer- 


Area. 


Diameter. 


Circumfer- 


Area. 




ence. 






ence 




A 


0.19G3 


0.0030 




4.5160 


1.6229 


X 
8 


0.3927 


0.0122 


"a 


4.7124 


1.7671 


A 


0.5890 


0.0276 




4.9087 


1.9175 


i 


0.7854 


0.0490 


8 


5.1051 


2.0739 


1-6 


0.9817 


0.0767 


H 


5.3015 


2.2365 


i 


1.1781 


0.1104 


* 


5.4978 


2.4052 


1 1> 


1.3744 


0.1503 


t| 


5.6941 


2.5801 


1 

2 


1.5708 


0.1963 


z 


5.8905 


2.7611 


A 


1.7G71 


0.2485 


JLA 
1 b 


6.0868 


2.9483 


ft 

8 


1.9635 


0.3068 








n 


2.1598 


0.3712 


2 in. 


6.2832 


3.1416 


a 

4 


a. 3562 


0.4417 


is 


6.4795 


3.3411 


n 


2.5525 


0.5185 


i 


6.6759 


3.5465 


8 


2.7489 


0.6013 


.a. 
i b 


6.8722 


3.7582 


if 


2.9452 


0.6903 


1 

4 


7.0686 


3.9760 








fg 


7.2649 


4.2001 


lin. 


3.1416 


0.7854 


1 


7.4613 


4.4302 


J b 


3.3379 


0.8861 


-h 


7.6576 


4.6664 


i 


3.5343 


0.9940 


X 
2 


7.8540 


4.9087 


-A 


3.7306 


1.1075 




8.0503 


5.1573 


X 
4 


3.9270 


1.2271 


ft 

8 


8.2467 


5.4119 


i b 


4.1233 


1.3529 


1 6 


8.4430 


5.6727 


h 


4.3197 


1.4848 


i 


8.6394 


5.9395 



218 



STEAM HEATING FOB BUILDINGS. 



Diameter. 


Circumfer- 
ence. 


Area. 


Diameter. 


Circumfer- 
ence. 


Area. 


13. 
i i 


8.8357 


6.2126 


i 


17.2788 


23.7583 


I 


9.0321 


6.4918 


ft 


17.4751 


24.3014 


15. 
1 li 


9.2284 


6.7772 


t 


17.6715 


24.8505 








11 
1 6 


17.8678 


25.4058 


3 in. 


9.4248 


7.0686 


3. 

4 


18.0642 


25.9672 


.1. 
1 6 


9.6211 


7.3662 




18.2605 


26.5348 


i 


9.8175 


7.6699 


i 


18.4569 


27.1085 


ft 


10.0138 


7.9798 


1 5 

76 


18.6532 


27.6884 


i 


10.2102 


8.2957 








.5.. 
1 6 


10.40G5 


8.6179 


6 in. 


18.8496 


28.2744 


t 


10.6029 


8.9462 


TiS 


19.0459 


28.8665 


JL- 

1 6 


10.7992 


9.2806 


i 


19.2423 


29.4647 


* 


10.9956 


9.6211 


ft 


19.4386 


30.0798 


Q 

16 


11.1919 


9.9678 


1 

4 


19.6350 


30.6796 


1 


11.3883 


10.3206 


.1 
1 6 


19.8313 


31.2964 


ft 


11.5846 


10.6796 


1 


20.0277 


31.9192 


2. 
4 


11.7810 


11.0446 


ft 


20.2240 


32.5481 


13. 

1 6 


11.9773 


11.4159 


J 


20.4204 


33.1831 


i 


12.1737 


11.7932 


YS 


20.6167 


33.8244 


if 


12.3700 


12.1768 


i 


20.8131 


34.4717 








n 


21.0094 


35.1252 


4 in. 


12.5664 


12.5664 


a. 

4 


21.2058 


35.7847 


i 
1 1? 


12.7627 


12.9622 


11 


21.4021 


36.4505 


i 


12.9591 


13.3640 


i 


21.5985 


37.1224 


A 


13.1554 


13.7721 


n 


21.7948 


37.8005 


i 


13.3518 


14.1862 








5_ 
1 6 


13.5481 


14.6066 


7 in. 


21.9912 


38.4846 


I 


13.7445 


15.0331 


ft 


22.1875 


39.1749 


.1. 

] 6 


13.9408 


15.4657 


i 


22.3839 


39.8713 


i 


14.1372 


15.9043 


ft 


22.5802 


40.5469 


1% 


14.3335 


16.3492 


1 

4 


22.7766 


41.2825 


a 

8 


14.5299 


16.8001 


1 6 


22.9729 


41.9974 


■H 


14.7262 


17.2573 


I 


23.1693 


42.7184 


4 


14.9226 


17.7205 


ft 


23.3656 


43.4455 


II 


15.1189 


18.1900 


J 


23.5620 


44.1787 


F 


15.3153 


18.6655 


ft 


23.7583 


44.9181 


if 


15.5716 


19.1472 


1 


23.9547 


45.6636 








H 


24.1510 


46.4153 


5 in. 


15.7080 


19.6350 


? 


24.3474 


47.1730 


ft 


15.9043 


20.1290 


it 


24.5437 


47.9370 


i 


16.1007 


20.6290 


I 


24.7401 


48.7070 


ft 


16.2970 


21.1252 


1 5 
16 


24.9354 


49.4833 


i 


16.4934 


21.6475 








.5.. 
1 6 


16.6897 


22.1661 


8 in. 


25.1328 


50.2656 


| 


16.8861 


22.6907 


i 6 


25.3291 


51.0541 . 


ft 


17.0824 


23.2215 


4 


25.5255 


51.8486 



MISCELLANEOUS NOTES AND TABLES. 



219 



Diameter. 


Circumfer- 
ence. 


Area. 


Diameter. 


Circumfer- 
ence. 


Area. 


A 


25.7218 


52.8994 


3. 

4 


36.9138 


108.4342 


* 


25.9182 


53.4562 


1 

a 


37.3065 


110.7536 


A 


26.1145 


54.2748 








1 


26.3109 


55.0885 


12 in. 


37.6992 


113.0976 


.1. 

1 6 


26.5072 


55.9138 


i 


38.0919 


115.4660 


i 


26.7036 


56.7451 


4 


38.4846 


117.8590 


To 


26.8999 


57.5887 


1 


38.8773 


120.2766 


f 


27.0963 


58.4264 


X 


39.27C0 


122.7187 


H 


27.2926 


59.7762 


I 


38.6627 


125.1854 


1 


27.4890 


60.1321 


It 
4 


40.0554 


127.6765 


if 


27.6853 


60.9943 


1 


40.4481 


130.1923 


8 


27.8817 


61.8625 








n 


28.0780 


62.7369 


13 in. 


40.8408 


132.7326 








* 


41 2338 


135.2974 


9 in. 


28.2744 


63.6174 


i 

4 


41.6262 


137.8867 


lb 


28.4707 


64.5041 


f 


42.0180 


140.5007 


* 


28.6671 


65.3968 


* 


42.4116 


143.1391 


T> 


28.8634 


66.2957 


"I 


42.8044 


145.8021 


1 

4 


29.0598 


67.2007 


4 


43.1970 


148.4896 


t% 


29.2561 


68.1120 


i 


43.5857 


151.2017 


1 


29.4525 


69.0293 








lti 


29.6488 


69.9528 


14 in. 


43.9824 


153.9384 


f 


29.8452 


70.8883 


i 


44.3751 


156.6995 


Vff 


30.0415 


71.8121 


i 

4 


44.7676 


159.4852 


1 


30.2379 


72.7599 


| 


45.1605 


162.2956 


1± 

J 6 


30.4342 


73.7079 


i 


45.5532 


165.1303 


i 


30.6306 


74.6620 


i 


45.9459 


167.9896 


*t 


30.8269 


75.6223 


if 


46.3386 


170.8735 


4 


31.0233 


76.5887 


i 


46.7313 


173.7820 


H 


31.2196 


77.5613 














15 in. 


47.1240 


176.7150 


10 in. 


31.4160 


78.5400 


i 


47.5167 


179.6725 


i 


31.8087 


80.5157 


* 


47.9094 


182.6545 


4 


32.2014 


82.5160 


1 


48.3021 


185.6612 


f 


32.5941 


84.5409 


i 


48.6948 


188.6923 


* 


32.9868 


86.5903 


f 


49.0875 


191.7480 


f 


33.3795 


88.6643 


i 


49.4802 


194.8282 


if 


33.7722 


90.7627 


I 


49.8729 


197.9330 


4 


34.1649 


92.8858 














16 in. 


50.2656 


201.0624 


11 in. 


84.5576 


95.0334 


i 


50.6583 


204.2162 


f 

4 


34.9503 


97.2053 


i 

4 


51.0510 


207.3946 


35.3430 


99.4121 


| 


51.4447 


210.5976 


t 


35.7357 


101.6234 


i 


51.8364 


213.8251 


t 


36.1284 


103.8691 


£ 


52.2291 


217.0772 


f 


36.5211 


106.1394 


1 


52.6218 


220.3537 



220 



STEAM HEATING FOR BUILDINGS. 



Diameter. 


Circumfer- 
ence. 


Area. 


Diameter. 


Circumfer- 
ence. 


Area. 


i 


53.0145 


223.6549 


1 


67.1517 


358.8419 








i 


67.5444 


363.0511 


17 in. 


53.4072 


226.9806 


I 


67.9371 


367.2849 


£ 


53.7999 


230.3308 


4 


68.3298 


371.5432 


$ 


54.1926 


233.7055 


1 


68.7225 


375.8261 


f 


54.5853 


237.1049 








i 


54.9780 


240.5287 


22 in. 


69.1152 


380.1336 


t 


55.3707 


243.9771 


i 


69.5079 


384.4655 


2. 
4 


55.7634 


247.4500 


X 
4 


69.9006 


388.8220 


1 


56.1561 


250.9475 


f 


70.2933 


393.2031 








£ 


70.6860 


397.6087 


18 in. 


56.5488 


254.4696 


4 


71.0787 


402.0388 


i 


56.9415 


258.0161 


f 


71.4714 


406.4935 


4 


57.8342 


261.5872 


4 


71.8641 


410.9728 


1 


57.7269 


265.1829 








i 


58.1196 


268.8031 


23 in. 


72.2568 


415.4766 


1 


58.5123 


272.4479 


1 


72.6495 


420.0049 


! 


58.9056 


276.1171 


4 


73.0422 


424.5577 


i 


59.2977 


279.8110 


f 


72.4349 


429.1352 








i 


73.8276 


433.7371 


19 in. 


59.6904 


283.5294 


f 


74.2203 


438.3636 


i 


60.0831 


287.2723 


a 

4 


74.6130 


443.0146 


4 


60.4758 


291.0397 


4 


75.0057 


447.6992 


$ 


60.8685 


294.8312 • 








i 


61.2612 


298.6483 


24 in. 


75.3984 


452.3904 


f 


61.6539 


302.4894 


1 


75.7911 


457.1150 


I 


62.0466 


306.3550 


i 

4 


76.1838 


461.8642 


* 


62.4393 


310.2452 


f 


76.5765 


466.6380 








£ 


76.9692 


471.4363 


20 in. 


62.8320 


314.1600 


f 


77.3619 


476.2592 


4 


63.2247 


318.0992 


4 


77.7546 


481.1065 


i 

4 


63.6174 


322.0630 


1 


78.1473 


485.9785 


I 


64.0101 


326.0514 








4 


64.4023 


330.0643 


25 in. 


78.5400 


490.8750 


1 


64.7955 


334.1018 


i 


78.9327 


495.7960 


4 


65.1882 


338.1637 


4 


79.3254 


500.7415 


4 


65.5809 


342.2503 


| 


79.7181 


505.7117 








i 


80.1108 


510.7063 


21 in. 


65.7936 


346.3614 


f 


80.5035 


515.7255 


i 


66.3663 


350.4970 


ii 

4 


80.8962 


520.7692 


4 


66.7590 


354.6571 


i 


81.2889 


525.8375 



To find the circumferences of larger circles, multiply the diameter 
by 3.1416. For areas, multiply the square of the diameter by 0.7854. 



MISCELLANEOUS NOTES AND TABLES. 221 
TABLE NO. 13. 

SHOWING THE NUMBER OF FEET IN LENGTH OF VARIOUS SIZED PIPES 
WHICH WILL CONTAIN ONE CUBIC FOOT OF WATER. 



Nominal Size 
of Pipe. 


Length in feet which 

will contain one cubic 

foot. 


Nominal Size 
of Pipe. 


Length in feet which 

will contain one cubic 

foot. 


i. 


470.0 


3* 


14.6 


a. 


270.0 


4 


11.3 


1 


1G7.0 


4i 


9. 


H 


96.5 


5 


7.2 


u 


70.5 


6 


5. 


2 


43.9 


7 


3.54 


3* 


30.0 


8 


2.875 


3 


19.35 


9 


2.26 



By multiplying the above lengths by the relative 
volume * of steam at any required pressure, it will give 
the length of pipe which will be necessary to contain a 
cubic foot of water when converted into steam at that 
pressure. 



* See Table No. 5. 



APPENDIX A. 

The following detailed specification is here introduced to 
familiarize the reader with an ordinary form for a steam- 
heating tvork, and will suggest much useful information to 
the fitter. 

SPECIFICATION 

FOR STEAM-HE ATING APPARATUS, VENTILATION", COOKING, 

WASHING, DRYING, AND PUMPS, FOR A HOTEL OR 

PUBLIC BUILDING. 

Boilers. There will be required for heating and power 

.... horizontal multi-tubular boilers, each inches in 

diameter and feet long, with lap- 
welded tubes ; inches in diameter, of No. . . wire- 
gauge iron, no tube to be placed nearer than three (3) inches 
to shell. 

steam dome. Each boiler will have a steam-dome 

inches high, and inches in diameter. 

Mad-pipes. The mud-pipes for boilers, (if used,) will be 
inches in diameter by six (6) feet long, with heavy- 
cast-iron connections. The connecting-pipe to be eight (8) 
inches inside diameter cast metal, not less than one (1) inch 
in thickness ; the head and flange will also be of cast-iron. 
The flanges and connections to have turned faces, and to be 



224 APPENDIX. 

fitted with three-fourth (J) inch bolts, not more than three 
(3) inches from centers. 

Lugs. Each boiler to have four (4) cast-iron lugs or 
brackets, one and one-fourth (1J) inch thick, and twelve (12) 
inches wide, and to project not less than twelve (12) inches 
from the sides of boilers. The lugs will be fastened to the 
shell of boilers with not less than ten (10) three-fourths (§) 
inch rivets each. 

Man-hoies. The man-holes of boilers will be twelve (12) by 
sixteen (16) inches, with heavy plate and guard. 

Hand-hoies. Each boiler will have two (2) hand-holes, of the 
ordinary size, provided with heavy plates and guards. 

Material. The whole shell, heads, dome, and mud-pipe to 
be of C. H. No. 1 iron (or boiler steel of the finest quality), 
each and every sheet used in construction of boilers must be 
stamped, showing the grade and quality of the iron or steel. 
The shell of boilers and domes will be five-sixteenths ( T \) 
of an inch thick. Heads three-eighths (§) inch thick. 
Heads of dome, three-eighths (f ) inch. The mud-pipe (if 
used) will also be three-eighths (§) of an inch thick. 

stays and Each head of boilers above the tubes to have not 

braces ] ess than braces or stays, each brace or 

stay to have in its smallest diameter one square inch of the 
best refined iron, and to be fastened to the shell and heads 
by the best method for equalizing strain. Heads of domes (if 
made of wrought-iron) to have stays or braces, sub- 
ject to the same conditions as aforesaid stays or braces. 

seams. Longitudinal seams to be double riveted. The 
vertical seams in dome, and flange of dome, to be double 
riveted. No hole larger than six (6) inches to be made in 
shell of boiler under the dome, the aggregate area of said 
holes to be four times that of the steam-pipe. 

Rivets. No cupped or button -set rivets are to be al- 
lowed — they must be either hand or machine made, the latter 



APPENDIX. 225 

preferred. The use of the drift pin must be entirely dis- 
pensed with. The splitting or cracking of a hole or sheet 
will be cause for rejection. 

calking. Where the work is chipped and calked after 
being fitted and riveted, it must be done in such a manner 
that the inside sheets will not be marked or seamed by the 
chisel or calking- tool ; the edges must be driven in straight, 
and not against, or partly against, the inner sheet, hereby 
raising a shoulder on it. 

Testing. Each of said boilers will be tested to one hun- 
dred and fifty (150) pounds cold-water pressure to the square 
inch before leaving the shops. The Supervising Engineer or 
Architect to have every facility for examining the work as it 
progresses. 

The boilers to be made in accordance with the drawings, 
special attention being paid to laying out the tubes. 

The non-compliance with any of the above will be cause 
for the rejection of any or all of the boilers. 

Boiler The boiler to be substantially set up in brick- 
setting. wor k . wa ii s inches thick, the 

foundation walls to be of stone, inches 

thick, laid in cement mortar. All exposed walls will be built 
of straight well-burned bricks, laid in fresh lime and sand 
mortar, all brick-work exposed to the fire to be lined with 
first-class fire-bricks, laid in fire-clay mortar, the floor of 
fire-pit will be paved with hard burned brick, and well grouted. 
Boiler fronts. Each boiler to have a full cast-iron front, the 
metal to bo five-eighths (|) inch thick. Said fronts will 
have flue doors, fire doors, and ash doors of sizes drawn, all 
neatly fitted. The fire doors will be lined with perforated 
plates to allow free circulation of air between the doors and 
linings. The boilers to be furnished with cleaning doors, 
covering-bars, anchors, bolts, tie-rods, buckstaves, and other 
castings usual and necessary. 



226 AP1ENDIX. 

smoke flaes. Each furnace to have flues leading from the 
front-connection of boiler, and connecting with a main flue to 

stack. Said flues to be of wrought-iron of an 

inch thick, thoroughly riveted and bolted at connections, the 
flues to be furnished with the required dampers. 

Grates. One set of grate bars will be required for each 
boiler as drawn. 
Boiler trim- Each boiler to be provided with a inch 

minga safety- valve, a two (2) inch blow-off cock, one eight 
(8) inch nickel-plated cased steam-gauge of approved con- 
struction, one three-fourths (f ) inch water-gauge, three com- 
pression gauge-cocks, with wooden handles, a one and one- 
half (1|) inch feed-pipe, together with all necessary pipes, 
valves, fittings, etc., to make the whole complete in all its 
parts ; the boilers to be so connected that they may be sepa- 
rately or together used for heating and all other purposes. 

Small pump. Provide and set up where specified or shown, two 
of Worthington's Duplex boiler feed-pumps, (or any other 
pump of approved qualities. ) Diameter of steam cylinders, 

inches ; diameter of water cylinder, 

inches ; length of stroke, inches. 

Pump con- ^ ne P um P s to be so connected and cross connect- 
nectious. e( ^ that either can be used for the work of the other. 

steam-pipes. All the pipes used for steam to be of wrought- 
iron, of standard weight and dimensions. Said pipes to be 
screwed together with heavy cast-iron fittings, and wrought- 
iron sockets. Cast-iron flange-unions to be used on all pipes 
larger than two (2) inches, and right-and-left couplings for 
pipes less than two and a half (2|) inches. 

The main steam-pipes to start from the dome of each 

boiler with a inch pipe and valve, and run to a 

cross-main, said cross-main to be inches. 

The main distributing-pipe for heating apparatus is to 
start from cross-main of inches in diameter, and 



APPENDIX. 227 

be run in or about the position shown on plans, and of the 
sizes there marked, and to be out less than two inches at 
each of its extremes, and furthermore, no engine-pipe, or 
elevator-pump pipe, must be taken from the same cross- 
main ; but must have separate connections to the domes of 
boilers, when used. 

Steam-mains to be supplied with all fittings, valves, etc., 
usual and necessary for the proper completion of the appar- 
atus. The further distribution of the steam-pipes and re- 
turns can be seen by consulting plans. 

Expansion ^ ne mam su Ppl.Y an d return pipes, also branch 
joints, mains and returns, will be supplied with the nec- 
essary expansion joints, when the expansion cannot be com- 
pensated for by right-angle turns. 

Rising mains. Each perpendicular line of coils or radiators will 
have a separate rising main. Not more than two (2) radia- 
tors to be supplied from one rising main on the same floor. 
The mains to be accompanied by a return-pipe, said return-pipe 
will be one size smaller than supply-pipe. The rising mains 
and return-pipes will each have a brass globe or angle-valve 
same size as pipes, at their lower ends, so that steam may be 
let on or off one or more sections without interfering with 
any other. 

Relief pipes. The main steam-pipes to be properly drained in 
suitable places, so that no water of condensation can at any 
time remain in pipes above the water-line. All pipes to be 
secured to walls, arches, etc., with expansion hangers and 
hooks, as may be required. 

Return pipes. The main return-pipes for collecting the water 
of condensation from the coils, radiators, and relief-pipes, 
must be of sufficient capacity to collect all the water and 
conduct it back. 

All return pipes must be supplied with valves, fittings, 
etc., to correspond to the main steam-pipe. 



228 APPENDIX. 

summer Summer supply-pipe will be required for the 
supply. -Qgg f ^ ne i ail ndry, kitchen, drying room, venti- 
lating shafts and hot-water tanks, said pipe to be connected 
to boilers direct, and so arranged that it can be supplied 
by steam from either boiler, separately and together. This 

pipe will extend to kitchen etc., inches in diameter, 

and will have globe-valves same size of pipes on each con- 
nection, etc., and the above specified pipe to have branches 
as drawn, with a brass globe-valve connecting each branch 
to main. 

summer re- Furnish and fit up return-pipes for collecting 
turn pipes. fae wa t e r of condensation from laundry, kitchen, 
coils in drying room, hot-water tanks, and coils in ventilating 
shafts, and return the same to boilers (or condensed steam-tank 
in boiler room, ) with all connections, valves, and everything 
necessary to finish the work. The return-pipes to be 
one size smaller than supply-pipes, each to be furnished with 
a brass Yalve same size of pipe. The whole system of sum- 
mer supply and return pipes to be entirely independent of 
the general steam-heating pipes. 

Valves. Valves of two (2) inches and under, to be made 
of the best steam-metal. The bodies of all valves, two and 
a half (2|) inches and upward, to be made of the best soft 
cast-iron, with valves, seats, and stems of steam-metal. 

Fittings. The fittings throughout the entire work, unless 
otherwise specified, must be of the best quality of cast-iron, 
neatly finished. 

Eadiators. All radiators used must be vertical tube radia- 
tors, made of wrought or cast iron with ornamental cast-iron 
tops and bases. 

All rooms in building, with radiators shown on plans, to 
have one or more of the above style of radiators, situated as 
near as possible to position marked on plan, and to have not 
less heating surface in square feet than is marked in figures 



APPENDIX. 229 

on plan of radiator, in each room. Each radiator above, and 
including eighty (80) square feet of heating surface, to have 
one and one-fourth (1J) inch steam-valves and connections, 
and one (1) inch return-valves and connections. Each ra- 
diator less than eighty (80) square feet, and more than forty 
(40) square feet of heating surface, to have one (1) inch 
steam-valves and connections, and three-fourths (J) inch 
return-valves and connections ; all smaller radiators to have 
three-fourths (J) inch steam and one-half (J) inch return 
valves and connections. Each radiator and coil throughout 
the work must be provided with an air-valve. Each radi- 
ator to be bronzed with the best quality of gold bronze. 
All radiator-valves to be nickel plated, and have wooden 
handles. 

coils. The .... floor will be heated with ornamental 

coil radiators of size and capacity marked on plan, and 
will have . . inch steam and . . inch return pipes and valves, 
the valves to be nickel plated. These coils will be finished 
with black baking japan, relieved with gold as may be 
directed. 
Horizontal ^ ie cna P e l an ^ dining-rooms will be heated 

coils. with horizontal coils of one (1) inch pipe, with 
amount of heating surface marked on plans in square 
feet, with spring-pieces at inlet ends, all to be provided with 
the necessary manifolds. The coils to rest on cast-iron ring 
plates not less than eight feet apart, said ring plates to be 
screwed to neat wooden strips, the strips being well fastened 
to walls and partitions, the brick walls to be plugged. All 
coils to be placed on the outside walls under windows. 

There will be put up in each ventilating shaft a coil of one 

(1) inch pipe equal to square feet of heating 

surface, with supply and return connections, also steam and 
return valves. The coils will be supported upon the re- 
quired hook plate. All the coils and pipes, both mains and 



230 APPENDIX. 

returns, will be painted with black baking japan, in best 
manner. 
Heating ^he maximum pressure of steam is not to exceed 
capacity, fifty (50) pounds to the square inch, and should 
the amount of heating surface figured on plans be found 
insufficient in any location of the building, through more 
than ordinary exposure, the heating surface may be in- 
creased to the necessary amount. The extra cost to be gov- 
erned by prices in schedule. 

VENTILATION". 

chapel and ^ n eacn °^ ^ our W mam ventilating shafts in 

wings, rotunda building will be placed 

square feet of heating surface, in one coil of one (1) inch 
internal diameter steam-pipe, fastened to the inside of shafts 
with the necessary hook plates and battens. 

Registers. To furnish the necessary registers, of the re- 
quired size, finished in black japan, and properly set up, 
and secured in the wall. 

Into these shafts the rooms will be ventilated ; as shown 
on drawings. 

All ventilating coils to be united to the summer supply 
and return pipes. 

Drying room. The drying room will be ventilated by a shaft 
with entrance from ceiling over clothes rack and connected 
by a lateral duct to boiler smoke stack (or elswhere). 

The supply of fresh air being admitted beneath the floor 
of drying-room by openings in the wall (between joists), 
through the floor, by perforations one and one-fourth (1J)- 
inch in diameter under drying-coils. 

KITCHEN. 

Meat kettles. To furnish and set up in the kitchen 



APPENDIX. 231 

steam kettles, for cooking meats, etc., each of seventy-five 
(75) gallons capacity, with all the cocks and valves necessary 
to complete the same. Make all connections for cold-water, 
steam, and return pipes of the full size of tapped hole, said 
pipes to be supplied with brass valves. 

vegetable ^° f um i sn and set up vegetable steam- 

ketties. ers f thirty-three (33) gallons capacity, with the 
necessary tin baskets, etc. Make the necessary connections 
with water, steam, and waste pipe, with valves and cocks 
of required sizes. 

sinks. To furnish and set up cast iron sinks 3 

feet by 3 ft. 6 in., and 10 inches deep, to be set as drawn, 
with J inch hot and cold water connections, provided with 
compression cocks of brass, and waste connection to sewer, 
2 inches internal diameter. 
Coffee-um. To furnish and set up one steam jacket tea and 

coffee maker or urn, of gallons capacity, with 

all the necessary steam and water connections, valves, etc. 

Hot-water To furnish and set up one hot-water boiler, . . . 
feet. . . inches in diameter by . . . feet high, made 
of one-fourth inch boiler plate, the top end to be riveted in, 
the bottom to be of cast-iron, bolted to wrought-iron flange. 
The boiler to be riveted, chipped, and calked, and to be 
tested to a pressure of one hundred and fifty (150) pounds 

per square inch. Said boiler to be provided with a 

coil of lineal feet of one (1) 

inch internal diameter steam-pipe, for supplying steam heat. 
Said coil to be connected to the cast-iron bottom of boiler, 
and to have the necessary supply and return pipes and 
valves. 

Vapor-pipe. Each steam kettle or steamer to have a vapor 
pipe, three (3) inches in diameter, connected to a six (6) 
inch main ; said main to be carried to the roof. 



232 APPENDIX. 



LAUNDRY. 



Washing- ^ ne laundry will be fitted up to run with steani- 
machines. p 0W er. To furnish . . large laundry-size wash- 
ing-machines with wringer and counter- shaft with the 
necessary belting, etc., to connect with line-shaft, machines, 
and wringers ; make all water connections (hot and cold), 
steam and sewer connections. 

soak-tubs. Furnish and set up .. soak-tubs, six (6) feet long 
by two feet eight inches (2 ft. 8. in.) wide, and two feet four 
inches (2 ft. 4 in.) deep. Soak-tubs to be made of two 
inch pine plank matched together, the joints being set in white 
lead ; the angles to be well spiked and secured with wrought- 
iron straps screwed on in best manner. The tubs to be 
made water-tight. The wash and soak tubs to be supplied 
with hot and cold water, and to be provided with a two- 
inch waste and overflow pipe connected with drain. The 
hot and cold water supply will be one (1) inch in diameter, 
with brass compression bibbs. Washing-machines and soak- 
tubs to have steam connections with at least four (4) feet of 
one-half (J) inch perforated brass pipe to each machine and 
tub, for the purpose of boiling the clothes, with all the 
necessary valves and fittings to properly finish the same. 

Mangle. To furnish and set up one (1) box (or French) 
mangle securely fastened to the floor of laundry, with the 
necessary counter- shaft, leather belting, pulleys, etc. Mangle 
pulley to be . . inches in diameter, by . . inches face, and to 
have a . . inch leather driving belt. The mangle to be prop- 
erly loaded and balanced ; speed of mangle pulley to be not 
less than revolutions per minute, nor over 



DRYING ROOM. 

steam-pipes. There will be required in the drying room of 



APPENDIX. 23S 

laundry coilg of one (1) inch pipe ten (10) feet 

long, and four (4) pipes high, set on hook stands, and each 
connected into a three (3) inch manifold, to be supplied with 

a inch steam pipe and valve on feed end, 

and a inch pipe and valve on return end; said steam- 
pipes to be connected with summer supply-pipe. 

clothes Furnish clothes racks, together 

racks, ^yith rollers, guides, handles, lines, and 

.... wrought-iron tracks for the same, to be made of three- 
sixteenths (j\) inch by three-fourths (§) inch rolled T-iron, 
twenty feet long, each, and to be screwed to the floor. All 
to be finished and set up, in accordance with the drawing, in 
good working order. The wood- work of clothes racks to 
be furnished and put up by the joiner, the work being 
done under the direction of the contractor, who will be held 
responsible for the proper working of the same. 

FINALLY. 

Mason and ^ ne brick and mason work, and all excavations 

brickwork. w j^ ^ e ^one by the builder (excepting the brick and 

mason work of boilers), and all material belonging to such 

work wall be furnished by the same. The materials for boiler 

setting will be provided by the contractor. 

carpenter ^ ie carpenter work for the entire apparatus will 

work - also be done by the joiner, and materials therein 

used furnished by the same. 

The contractor will be held to furnish all of the different 
kinds of pipe 'herein stated, and the necessary quantities of 
each kind ; he will furnish all other materials as herein 
specified ; he will do all work which is required of him in 
these specifications. All materials and all work must be of 
the best quality and done in the most workmanlike manner. 
All openings or slats in the walls required to be cut for any 
pipe, must be done by the contractor, if not otherwise pro- 



234 APPENDIX. 

vided for, and any injury to plastering, or wood-work, in the 
different buildings, must be borne by him, and made good 
at his own expense, and in no case shall any cutting be 
allowed without the permission of the architect. 

It is to be distinctly understood, that the true meaning 
and intent of these specifications are, that the whole work 
shall be performed in the finest and most secure manner. 

All disputes arising from these specifications to be sub- 
mitted to a board of 3, selected as follows: — The contractor 
to select one, the owner or architect to select one, and the 
two thus selected to choose a third — the decision of the 
majority to be binding on both parties. 



APPENDIX B. 



PLUKAL BOILER SPECIFICATION. 

BOILERS FOR HEATING, ETC. 

General. To furnish and set up in the Boiler House 
set apart for that purpose .... Horizontal multi-tubular 

Boilers long by inches in diameter, 

and to contain tubes feet long, with a 

dome on top of each shell diameter by ... . high, 

measuring from the top of the shells, and with a man- 
hole on the top of each shell back of the dome ; the 
man holes to be 15 by 11 inches and to be set with 
their greatest diameters across the shells and a hand- 
hole 3 1 by 5 inches in each head of each boiler. 

BOILER SHELLS. 

Material. The shells of said boilers to be made of the 
best .... steel or any other homogeneous steel accept- 
able to the . . . . ; samples of which when cut at random 

Quality, from the edges of the sheets must bear bending 

cold (completely doubling on themselves and hammered 

Thickness, close) without sign of fracture. The said shell 

seams, to be full inch in thickness, and have but 

one longitudinal seam to each course ; the seam to be in 
the upper side of the shell in each course. 

Heads. The head sheets of said boilers to be one- 

235 



236 APPENDIX 

half inch thick and of the same makers' best flange steel 
as the shells. 

Domes. The domes of said boilers to be made of 

inch steel, with the heads of .... inch steel, thoroughly 
and properly braced, or of cast iron, thickness and weight 

of metal acceptable to the and approved by ... . 

Bracing The heads of said boilers to be braced in 
the best manner to equalize strain, the number of braces 

to each head to be not less than nor to be less 

than one inch in diameter if made of round iron, or its 
equivalent in cross-sectional area if made of any other 
shape iron. 

These braces and their crow-feet or legs to be made 
of best Swedish iron, and to be fastened to the heads 
and shells with not less than two |-inch rivets to each 
end of each brace. . 

Riveting. All longitudinal seams in the boilers to be 
double riveted ; the rivets not to be staggered, and the 
seams in the side of the dome, as well as the seams 
uniting the dome to the shell, to be double riveted, 
and all other seams to be properly riveted — machine 
rivets preferred. 
chipping and All seams of the boilers to be properly 

caikmg. c hipp e( j an d calked (Connelly's calking pre- 
ferred) ; a furrow from the chipping chisel or 
calking tools on any part of a boiler being 
cause sufficient for its rejection. The breaking or split- 
ting of a hole from drawing with drift pins or otherwise, 
or a crack or flaw or burn in or from the process of flang- 
ing, will be deemed sufficient cause for rejecting the 
boiler. 
Shells under The shells of the boilers underneath the 

Domes. d ome s are not to be cut out in one large piece, 



Injury to 
plates. 



APPENDIX. 237 

but to be a number of 2-inch holes aggregating not less 

than square inches, the bridges between any two 

holes to be not less than two inches. 

Special attention must be paid to this ! 
Expanding. The boiler tubes to be expanded with a 
" Dudgeon " expander, with the extension beyond the 
heads of uniform length, and not broken or ragged by a 
chipping chisel, but cut with some " cutting-off tool " at 
the end last expanded. 

Lugs. The boilers to be furnished with four cast- 

iron lugs or brackets for the purpose of supporting the 
same in brick-work ; these lugs to project from the side 
of the boilers not less than ten inches, and to have a 
projection below the plane of the brackets with three 
rivets in this lower projection, and with the usual com- 
plement above. If it is necessary to leave the lugs off 
the boilers until such time as they are in the basement 
of the building, a shoe must be riveted to the shell in 
lieu of the brackets, before the tubes are set, into which 
the lug will slip. 

Man-hoic. The man-hole casting to be extra heavy, with 
frame, plate, guard and bolt subject to the approval 
of the 

Hand-hoies. The hand-holes to be furnished with plates, 
bolts and guards ; the guard on rear hand-holes to be 
" turtle-backed," with a projection around the nut to 
protect them from the flame. 

rianges. The pipe flanges on the domes to be of the 
sizes marked on drawing and in the positions marked, 
and to be riveted to the domes and chipped and calked 
on the inside and set true with the axis of the boilers. 
A . . inch flange to be placed at the rear end of the 
rear course of the shell, at the bottom side, and to be 



238 APPENDIX. 

set true and riveted and chipped and calked. A 2-inch 

Holes in pipe n °l e *° be drilled and tapped into the 

heads. rear head and 1-|- in the front head where shown. 

CAST-IRON BOILER FRONTS. 

The boilers to be furnished with full cast-iron fronts 
of good and approved pattern, with planed and properly 

Design, fitted doors. The front connection doors pref- 
erably to swing sidewise, but should the design offered, 
and otherwise approved of, have lifting doors they will 
be accepted. 

Doors. The fire doors to be arched and of the sizes 
shown, and to have a heavy fire lining of cast iron. The 
ash pits to be furnished with doors, either sliding or 
swinging, and about the size as shown. 

In addition thereto to furnish the fronts and boilers 
with grates of size hereafter mentioned, and with all 
other castings, bolts and anchors necessary and usual 
for the proper completion of the masonry. 
Buckstaves The buckstaves to be .... feet .... inches 
in length, with not less than four-inch face and four-inch 
ribs and of the number required. The tie rods to be 

in length and *. . . in number. The dead 

plates to be 15 inches wide from the front to the end of 
the grate-bar, and to be not less than one inch thick. 
If the front-bearing bars and dead plates are not com- 
bined, the plates must be reinforced on their under side 
with a rib. 

Bearing-bars. The back bearing-bars to be a cast angle- 
iron one-inch thick, with three-inch flanges, as shown. 
The cleaning-doors to be heavy, and planed, and fur- 
nished with a lining and with latches. Should covering 



APPENDIX. 239 

bars be required for flues or elsewhere in connection 
with the boiler setting, they are to be furnished. 



BOILER SETTING. 

Boilers to be set on substantial stone foundation, and 
at proper level, the side walls of which are to be of the 

Bricks, best common bricks, properly and closely laid 
in fresh mortar of approved and best quality for this 
particular construction. 

Furnace. The furnace and all the parts acted upon by 
the flame to be lined throughout, and as per drawing, 
Firebrick. wi*h best quality of firebrick one course thick, 
laid on their flat and rubbed close together ; using 
only sufficient fire clay mortar to get an even bearing. 
Bridge-wall. The bridge-wall to be formed with beveled 
fire bricks, so as to give the required and necessary in- 
verted arch with close joints. The arch over the back 

Beveled connection to be formed with beveled fire- 

Bricks. b r i c k s suitable to the circle. 

In no place must the brickwork rest on the boiler. 

The boiler to be arched over the top, and the space of 

one inch maintained between the arch and the boiler. 

Lug In the brick . walls underneath the boiler 

Rollers. j U g S there must be placed bars of iron 14 in. 
wide and \ in. thick, to extend the whole distance 
between the lugs on a side. The six courses of fire- 
bricks underneath these irons to be " Headers." 

The front lugs to rest directly on these bars, but the 
rear ones to rest on 1^-in. rollers placed on the bars to 
admit of slight lateral motion ; care being taken that the 
brickwork and mortar will not in any manner interfere 
with the rollers or brackets. 



240 APPENDIX. 

waiis. The walls between the boilers to be in. 

thick. The boiler walls on the outside to be in. 

thick, with the bridge-wall in. thick. These 

thicknesses include the fire-brick linings. These walls 
to be built solid, and no walls or brick-work of the 
boilers to have the so-called air space. 

coping. The tops of boiler walls to be furnished with 
a 12-in. stone coping not less than 3 in. thick. In all 
cases where this specification on masonry may not be 
sufficiently explicit, the drawing must be followed. 



is 

Published Every Thursday, 

AT 140 WILLIAM STREET, NEW YORK. 



It maintains a Department of special interest to those interested in Heating 
Steam and Hot Water. In fact, more valuable information on 
this subject has appeared in its columns than in all 
other publications combined. 



" Whatever fault may be found on this side of the Atlantic with the newspaper press of 
America, it is an undoubted fact that tliat portion of the periodical literature of the United 
States which is devoted to science, occupies a most distinguished place amongst the scientific 
press of the globe. The Sanitaky Engineer stands high in this respect. In its pages the 
various subjects relating to public health— drainage, water supply, ventilation, heating and 
lighting— are most conscientiously attended to, shortcomings and abuses being fearlessly 
exposed, and care beinu' taken to have all expressed opinions upon technical matters prepared 
or revised by specialists."— Iron, London, Jan. 12. 

Sold by Newsdealer 6. 7 GenU a Gojiij. 

SUBSCRIPTION, $3.00 PER ANNUM, POST-PAID. 

SAMPLE COPY FREE. 



A CARD. 

The undersigned desires to call attention to the special branch 
of engineering to which he is professionally devoted — namely, 
Domestic Engineering — in which is included Ventilating, Warm- 
ing by Steam or Hot Water, Boilers, Engines and the construction 
of Laundry and Drying facilities. 

Having no connection with any firm or interest in any system, 
I beg to offer my services as a Consulting Engineer in the branches 
indicated, believing that 18 years' experience will enable me to 
render assistance that tvill be of value. 

WM. J. BALDWIN, 

96 Fulton St., New York. 

Author of "Steam Heating for Buildings," and Mem. Soc. Mech. Engineers. 



No. 71 Beekman and Fulton Sts., N. Y. 



LEAD 





NEW YORK MARKET FOR 

Steam and Gas Fitters. 
Machinists, Railroad and 
Factory Supplies. 

Nason's Patent Free- 
End Tubular Boilers. 

Nason's Patent Vertical 
Wrought-Iron Welded 
Tube Radiators. 

Nason's Patent Steam 
Trap Condensers. 

Nason's Patent Open 
Jaw Pipe Vise — will take 
Pipe at any point. 

Nason's Patent Improv- 
ed Glue or Paste Heater. 

Nason's Patent Combi- 
nation Boiler, with Worth- 
ington Steam Pump. 

Nason's Improved Draft 
or Damper Regulators. 

Nason's Improved Feed 
Water Heaters. 

Nason's Improved Foot 
Rail Brackets. 

Nason's Improved Ven- 
tilating Fans, for Hospitals 
and Public Buildings. 
Nason's Improved Boiler Feed Pumps. 
Nason's Improved Foot Valves with Strainers. 
Nason's Improved Water Columns, new design. 
The Worthington Steam Pumps, 
Water Meter. 
Bailey's Fire Hydrant. 

Wrought and Cast-Iron Pipe, all varieties, 
Valves, Cocks, Fittings, etc., for Steam, Gas, 
Water and Oil. 

Heating Apparatus for Public Buildings, Apart- 
ment Houses, Residences, etc. 



Established by Joseph Nason, 1840. 
Incorporated by The Mason Manufacturing Co., 1874. 

Carleton W. Nason, Harry F, Worthington. John W. Carrlng'on, 
Prest. Vice-Prest. Trcas. 



MANUFACTURERS OF 



Wrought Iron Pipe 

AND FITTINGS 

For Steam, Gas and "Water, 

LAP WELDED BOILER TUBES, 

Brass and Iron Valves and Cocks, 

CAST IRON RADIATORS, 

Fitters' Tools and Supplies 

OF EVERY DESCRIPTION. 

142 k 144 Centre St. and 117 Walker St., 

NEW YORK. 



Malleable Iron Fittings a Specialty. 



■w- s. :o 



TJlSTT'tS 



IMPROVED UNIVERSAL FORGE PUMPS. 



The undersigned begs to offer a new line of 
the above Pumps, which combine all the im- 
provements that a long experience has sug- 
gested. These Pumps have an increased 
stroke, greater power, superior finish, and 
oeauty of design. They can be placed in any 
desired position, as the working head rotates. 

The upper nozzle offers a straight water-way 
through the pump, saving much friction when 
filling a tank. Hose can be used at either 
nozzle if desired. A full assortment of these 
Pumps constantly on hand, for the house and 
for out-door wells of the greatest depth. For 
power and reliability, these pumps cannot be 
surpassed. 

Complete outfits furnished to order, and ad- 
vice given on all questions relating to water 
supply. Send for circulars. 



94 Beekman St., N. Y. 




WROUGHT-IRON PIPE 



Maeaiie m F 



iigs for Steam Heating. 



CHAPMAN VALVES. 



PAHCOAST k TARR, 

MANUFACTURER'S AGENTS, 

28 JPlcLtt Street, JSTew TorTc. 



WALWORTH MANUFACTURING COMPANY. 



Established 1842. 



Walworth 

J. J. Walwoeth 



?h?^ s co.I Capital, $400,000. 



Steam Engineers and Contractors. 

Plans and Estimates prepared for every description of Steam and Hot- Water 
Warming and Ventilating Apparatus. 

FOUNDRIES 



OFFICE, 

Salesroom and Engineer's Dep't, 

69 Kiy St, 

BOSTOJV. 



WW Warming of Dwelling 
houses and Green-houses by 
Hot Water a specialty. 




And MACHINESHOPS 

AT 

City Pol, 

Soufli Bostt 



Wrought- Iron Radiators. 



We manufacture all 
Radiators, Valves and Fit- 
tings used by us. 



GASKELL, GREENLIE &-CO. 

SUCCESSORS TO R. S. PLACE, 

Screw Bolt Manufacturers, Machinists and Shipsmiths v 

499 WATER & 253 SOUTH STS., NEW YORK. 

Bolts, Nuts, Wood Screws, Tap Bolts, Set Screws, Rivets. Washers, etc.. etc., constantly on 
hand and made to order at the shortest notice. Also, General Smith Work. 



Estimates given on Heavy and Light Forging. 



All kinds of Repairs promptly attended to. 



E. HOLLOWAY, 

CUwvy mux 414 W«e'r Bfs« 9 2ff« *W» 9 

Steam, (Pipe Sender. 

Coils of all Sizes anl Stapes for Oil Refineries, 

(Soap XLettxes, Heaters for Steam Boilers. 
RESIDENCE, 38 DIVISION ST., near Myrtle Ave., BROOKLYN. 



ANNIN & CO. IMPROVED STEAM HEATER. 



FiftS. 




The increasing: demand for Steam Heaters in dwellings has induced ns to make such 
changes and improvements in the construction of our apparatus as to enable us to place on the 
market, at a greatly rednced cost, what we can very safely say is the most complete and econ- 
omical Heater in use for Steam Heating Purposes. The fact of its having been in use for 
twelve years without getting out of repair is a sufficient guarantee of its durability of 
construction. 

It is entirely self-regulating, and so constructed that a circulation of the water in its steam- 
gnncrating space is constantly maintained. Any domestic of ordinary intelligence can take 
charge of it. 

As to its high efficiency, safety and simplicity of management, we would refer the public 
to a number of parties having them in use. 

Our large sizes as shown in Fig. 1, are for heating large dwellings, churches and schools, 
and are set in brickwork 8 inches thick; the inner course being built up circular to conform to 
the shape of the Heater. The Fire Pot is of cast iron, in four (4) sections, with water space 
around it, or in some cases of circular fire brick. The Grate is of the shaking and dumping 
pattern. The Steam and Water Drum surmounts an annular seriesof wrought iron tubes welded 
up at the lower ends as shown in Fig. 1. 

Fig. 2, for heating small houses, stores, etc. ; the construction being the same as Fig 1, 
except that it is encased in heavy sheet iron instead of brick ; the Fire Pot being in one casting, 
it takes up but very little space and is complete in every particular. 

For further particulars and circular address, 

jk. isr 3sr 1 3xr c*3 oo.„ 



Brooklyn Tube Works, 



Foot Adams Street, Brooklyn, 



THE RUSSELL VALVE. 

It is needless to remind steam users of the annoyance and actual loss entailed by the great 
quantities of cheap and worthless articles sold and put in as Globe Valves. Unless specified, no 
contractor can be expected to pay the cost of a reliable article. 

The It US SELL VA1. VE has stood the test for nine years. It has a composition mov- 
able disk that usually will last about two years, and can any time be readily replaced. 
MANUFACTURED ONLY BY 

T. R. McMANN & BRO, 

(Successors to McMann & Russell,) 
MANUFACTURERS AND DEALERS IN 

Wroaght-Iroa Pipe and Brass and Im Fittings 

FOR WATER AND STEAM, 

86 m 18 Gold Ste©et f If ©w ¥"o»&« 

Architects, and others interested, are requested to send for Descriptive 
Catalogues. 




83 Beekman St., N. Y. 



64 Union St., Boston. 



D. SAUNDERS' SONS, 




Pipe Cutting and Threading Machines, 

TAPPING MACHINES, 

STEAM AND GAS FITTEKS' HAND TOOLS, 

225 to 31 iSLtliertozi J5t., Yonkers, 3>3". "3T. 



BATES & JOHNSON, 



(Successors to WYLLTS H. WARNER,) 



MANUFACrOTtEnS OP 




STEAM WARMING 

APPARATUS, 

HIGH AND LOW PRESSURE. 



Sectional view of Magazine Boiler. 



BQILESS, RADIATOES, AUTCMATIC WATEB FEEBEBS, 
EBAFT REGULATORS, Etc, 

Sole manufacturers for New England, Eastern 
New York, Pennsylvania and New Jersey, of 

BATES' 

Patent Magazine Boilers. 

No. 114 LeonardSt, New York. 

Also, 33 West Railroad Street, Syracuse; 
310 Broadway, Albany. 



STEAM HEATING 

LOW OR HIGH PRESSURE. 



TWENTY-FIYE YEARS EXPERIENCE. 



Many hundred examples of our -work may be seen in New York and vicinity, 
including- the Stock Exchange Building and Drexel Building, Broad and Wall 
Sts.; the Catholic Cathedral, 50th St. and 5th Ave.; the Kelly Building, Beek- 
man and Nassau Sts.; and tho J. J. Astor Block, Broadway and Prince St.; 
also stores public buildings and private houses in Troy, Albany, Washington, 
and Memphis, Tenn. 

OILLIS & GEOGHEGAN, 

I 16 & I 18 WOOSTER STREET, 

ABOVE SPRING STREET N" K "W YORK, 



NATIONAL II 




MANUFACTURERS OF BEST QUALITY 




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FROM £ TO 15 INCHES DIAMETER. 



We make a sjpeeialty of Wroughi-Iron (Pipe and 
(Boiler Tubes for Steam Heating. 



Extra and Double Extra Strong Pipe for Coils 
and Heavy Pressure. 



MACK'S PATENT INJECTOR OR BOILER FEEDER. 



OPFIOES : 104 and 106 John Street, New York. 8 Femberton Square, Boston. 

159 Lake Street, Chicago. McKeesport, Pa. Pittsburg, Pa. 

WORKS : Boston, Mass. McKeesport, Pa. 



Frederick Townsend, Pres't. 



Jas. H. Blessing, Scc'y and Treas. 




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GRAVITATING 



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Bucket Trap. 



BUCKET 

RETURN 
STEAM 

TRAPS 




For Retail tie Waters of Conaensation. 

These Traps automatically drain 
the water of condensation from 
Heatixg Coils, and return the same 
to the Boiler, whether the Coils are , 
above or below the water level in 

Boiler, thus doing away with pumps gravitating Trap. 

and other mechanical devices for such purposes. They return the 
escaping steam of the brew-kettle, and thus effect a great saving 
in fuel. 

"Write for Circulars and prices to 

THE ALBANY STEAI TRAP COMPANY, 



THE M. T. DAYIDSOH 

IJ\£PRO ~VE<D 

STEAM PUMP, 



MANUFACTURED BY 



DAVIDSONS STEAM PUMP CO, 

41 to 4-7 Keap St., Brooklyn, N. Y. 




The above cut ■represents our regular Pressure or Boiler Feed Pump. We 
)umps for any situation where one can be used, and we positively assert that 
the M. T. Davidson Steam Pump is the 07tly one made, Single or Duplex, that 
can be run at high piston speed without shock and with safety to machine. This 
feature makes it the most desirable for Hotels, Hospitals, Apartment Houses, or 
any situation where quiet is a desideratum. 



American Laundry Machinery Co., 

8 New Church St., New York. 

WASHiKG MACHINES, 

Steam, Gas and Cold Mangles, Centrifugal and Roll 
Wringers, Collar, Cuff and Shirt Ironing Machinery. 

LAUNDRIES FITTED UP COMPLETE. 

EAST RIVER SCREW BOLT WORKS, 

WILLIAM GASKELL, 

MANUFACTURER OF 

Sm Mis, Ms, lap Mis, Ml taws, lit., 

No. 433 EAST 25th STREET, 

Near First Avenue, NEW YORK. 



FRED. STONE & CO., 

62 Gold St., New York. 

LMlowValyes and Hydrants, 

PIPE TONGS, 
Globe and Radiator Valves, Steam Cocks, etc, 




Jobbing Trade Solicited. 



Send for Price List. 



josinsr ^k.. scoll^ 

MANUFACTURER OF 

HOT WATER APPARATUS, 

For Warming Greenhouses, Dwellings, Baths, etc. 




Especially adapted for Varnish Factories, etc. 

Where a steady temperature is required. 

PLUMBING, STEAM AND GAS FITTING. 

SCOLLAY'S PATENT PLANT SPRINKLERS, 

For Window Gardens, Bouquets, Florists, etc. 

NOS. 74 & 76 MYRTLE AVENUE, BROOKLYN, N. Y, 




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This Coil will do the work of ordinary Indirect Radiators or Box-Coils in less 
than one-half the space. 

It is lighter, and at the same time stronger and more durable than any other. 

It is enclosed in casing- ready to set up, thus saving one-half the expense of 
erection. 

The circulation is perfect, the steam making but one turn, before it enters the 
bottom pipe. 

It is impossible for a volume of air to pass through this heater stack without being 
completely and promptly warmed, as the main current is broken into innumerable smaller 
currents by means of the hot coils ; these coils by reason of their elastic force and spiral form, 
closely embrace and press the pipe at every point of contact iherewith, thereby securing a 
great amount of extended heating surface of the most effective kind. 

The " Compound Coil " Radiator is confidently offered to the trade, confirmed by indis- 
putable evidences of its superiority, by numerous severe tests in competition with 
other well-known kinds, and also by its splendid performance in many private and 
public buildings. 

For further particulars and circular, address 

SAMUEL F, GOLD, Inventor and Manufacturer, Englewood, New Jersey. 



Hires Stem Hsatiae Co. 



Foundry : 

We st field, 31ass. 




Office and Boiler Works: 

Buffalo, JUT. Y. 

MANUFACTURERS OF 

THE PIERCE 

Wrought Iron 

STEAM HEATER 

AND 

Excelsior Indirect 

RADIATOR. 



This STEAM HEATER 
requires as little attention 
and less fuel than any 
other. 

fl^-SEND FOR CATALOGUE WHICH FULLY EXPLAINS ITS POINTS OF EXCELLENCE AND MERIT. 




The Excelsior Indirect Radiator. 

SIMPLE, EFFICIENT and CONVENIENT. 

Circulation of Steam is Positive. All Sections are Exactly Alike. 




LlOtifiglmb. 

MANUFACTURERS OF 

STEAM HEATING APPARATUS 
FOR THE TRADE. 



SOLE MANUFACTURERS OF THE 

BUNDY PATENT 

Direct and Indirect 

BA1IATOES 

Equally Adapted to High or Low Pressure, for Heating 
all Classes of Buildings by Steam. 

449 to 459 COMMUNIPAW AVENUE, 

JERSEY CITY, N. J. 



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I*±X3L Indirect Angle 

RADIATOR. 



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